Test the gate without three ONNX files (V-487)

keywordGate is an interface so the decision that ships an utterance can be
exercised with a fake that fires on demand. A gate that can only be tested
with a model file is a gate nobody tests.

The three that carry the fixed-when criterion: keywordless speech never
reaches STT, the keyword does, and barge-in still cuts her off mid-sentence.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013ptwopxyo3Z2kwFckHkLvN

cmd/mavwaked/main.go

@@ -12,10 +12,17 @@
 // samples and the capture frame is 480, so silero.go re-chunks. This comment
 // used to say the two matched, which was true of silero v4.
 //
-// There is still no wake-word model, so anything spoken near the microphone
-// becomes a turn (V-487 stage two). The SurfaceVoice auth layer caps all
-// commands at L0 (no destructive acts), which is what makes an accidental
-// trigger safe rather than expensive.
+// The keyword is "Мэйвен" and it is required, when -wake-model points at the
+// head (V-487 stage two). Without it anything spoken near the microphone
+// becomes a turn, which the SurfaceVoice auth layer makes safe rather than
+// expensive: it caps all commands at L0, no destructive acts. It does not cap
+// reading, so an open gate still lets the room hear his facts read back.
+// wakeword.go holds the cadence and wakefeatures.go the three models.
+//
+// The conn carries both directions. mavwaked sends utterances and receives
+// proactive nudges on it, and it is opened at startup rather than at the first
+// utterance, because mavend registers a voice session on accept. See nudge.go
+// for why a nudge that is not heard is worse than one that is not delivered.
 //
 // While a reply is playing the capture side is muted (half-duplex): without
 // it, Maven's own voice comes back in through the mic and she answers
@@ -57,6 +64,12 @@ const (
 	defaultAddr     = "127.0.0.1:9100"
 	defaultLang     = "ru"
 	defaultReadSize = 4096 // max PCM bytes per read from arecord (fits multiple frames)
+
+	// defaultWakeWindowMs — how long the keyword stays good for. He says
+	// "Мэйвен" and then a sentence, and the VAD does not close the utterance
+	// until he stops, so this has to outlive the word by the length of what
+	// follows it. It is spent on dispatch: one keyword, one turn.
+	defaultWakeWindowMs = 8000
 )
 
 func main() {
@@ -81,12 +94,18 @@ func run(args []string) error {
 	vadModel := flag.String("vad-model", "", "silero-vad onnx file; empty runs the energy threshold instead")
 	vadThreshold := flag.Float64("vad-threshold", defaultSileroThreshold, "speech probability a frame must clear")
 	onnxLib := flag.String("onnx-lib", os.Getenv("MAVEN_ONNX_LIB"), "libonnxruntime.so, needed with -vad-model")
+	wakeModel := flag.String("wake-model", "", "keyword head onnx; empty ships every utterance, as before V-487")
+	wakeMel := flag.String("wake-mel", "", "melspectrogram.onnx, required with -wake-model")
+	wakeEmbed := flag.String("wake-embed", "", "embedding_model.onnx, required with -wake-model")
+	wakeThreshold := flag.Float64("wake-threshold", defaultWakeThreshold, "score the keyword must clear")
+	wakeWindowMs := flag.Int("wake-window-ms", defaultWakeWindowMs, "ms an utterance may still start after the keyword")
 	flag.CommandLine.Parse(args)
 
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)
 	defer stop()
 
-	// Voice client — reused across utterances; SendRequest reconnects on error.
+	// Voice client — one conn carrying both directions. SendRequest reconnects
+	// on error, and the push receiver redials on its own clock.
 	vc := voice.Dial(*addr)
 	defer vc.Close()
 
@@ -165,6 +184,29 @@ func run(args []string) error {
 	}
 	sess := newSession(vad, newAplayPlayer(), &voiceSender{vc: vc}, *lang, barge)
 
+	// Keyword gate. A model that will not load is logged and not fatal, for
+	// the same reason silero's is not: an open gate is the daemon he had
+	// yesterday, and a daemon that refuses to start is not.
+	if *wakeModel != "" {
+		w, err := newWakeWord(*wakeMel, *wakeEmbed, *wakeModel, *onnxLib, *wakeThreshold)
+		if err != nil {
+			log.Printf("mavwaked: wake word unavailable, every utterance is a turn: %v", err)
+		} else {
+			defer w.Close()
+			sess.UseWakeWord(w, time.Duration(*wakeWindowMs)*time.Millisecond)
+			log.Printf("mavwaked: wake word from %s, threshold %.3f, window %dms",
+				*wakeModel, *wakeThreshold, *wakeWindowMs)
+		}
+	}
+
+	// Listen for nudges alongside capture. Connect eagerly so mavend has a
+	// voice session before he has said anything: without one, a nudge routed
+	// to voice finds nobody home and goes to the away channels instead.
+	if err := vc.Connect(ctx); err != nil {
+		log.Printf("mavwaked: voice server not reachable yet, retrying in background: %v", err)
+	}
+	go runNudgeReceiver(ctx, vc, sess)
+
 	return captureLoop(ctx, src, sess)
 }
 

cmd/mavwaked/nudge.go

@@ -0,0 +1,79 @@
+package main
+
+// The receiving half of the voice reach (V-671).
+//
+// mavwaked used to send and never listen. It wired no PushHandler, and
+// SendRequest discards a push frame when there is none. The consequence was
+// not a missing feature but a silent one: mavend routes a nudge to the voice
+// session that spoke most recently, and once mavwaked had spoken once it WAS
+// that session. PushToMostRecent succeeded, the dispatcher counted the nudge
+// delivered and stopped rerouting to telegram and ntfy, and mavwaked threw the
+// audio away. He heard nothing, anywhere.
+//
+// So the connection is opened at startup rather than at the first utterance,
+// and it is held open. A client that has never connected has no session, and
+// the dispatcher must be able to tell "he is not at the machine" from "he is,
+// and she has nothing to say".
+
+import (
+	"context"
+	"encoding/json"
+	"log"
+	"time"
+
+	"github.com/kami/maven/internal/voice"
+)
+
+// nudgeRetry is how long to wait before dialling again after the conn ends.
+// mavend restarts on every deploy, and a listener that gives up then is a
+// listener that is deaf until the next reboot.
+const nudgeRetry = 5 * time.Second
+
+// nudgeHandler decodes a push and hands the audio to the session, which
+// speaks it through the same player the reply path uses. It does not play
+// anything itself: the half-duplex gate and barge-in live on the capture
+// loop, and a nudge has to sit under both.
+type nudgeHandler struct{ sess *session }
+
+func (h *nudgeHandler) OnPush(p voice.Push) {
+	if p.Kind != voice.PushKindAudioNudge {
+		log.Printf("mavwaked: ignoring push of unknown kind %q", p.Kind)
+		return
+	}
+	var ap voice.AudioNudgePush
+	if err := json.Unmarshal(p.Params, &ap); err != nil {
+		log.Printf("mavwaked: nudge: decode: %v", err)
+		return
+	}
+	log.Printf("mavwaked: nudge from rule %q (severity %d): %q (%.2fs audio)",
+		ap.RuleName, ap.Severity, ap.Text, ap.Audio.Duration())
+	if len(ap.Audio.Bytes) == 0 {
+		// mavttsd was down or the text was empty. Say so rather than going
+		// quiet: the dispatcher already counted this one as delivered.
+		log.Printf("mavwaked: nudge %q carried no audio, nothing to speak", ap.RuleName)
+		return
+	}
+	h.sess.Nudge(ap.Audio)
+}
+
+// runNudgeReceiver keeps a push handler wired for as long as ctx lives,
+// redialling whenever the conn ends. Returns when ctx is cancelled.
+func runNudgeReceiver(ctx context.Context, vc *voice.Client, sess *session) {
+	h := &nudgeHandler{sess: sess}
+	for {
+		err := vc.RunPushReceiver(ctx, h)
+		if ctx.Err() != nil {
+			return
+		}
+		if err != nil {
+			log.Printf("mavwaked: nudge receiver: %v", err)
+		} else {
+			log.Printf("mavwaked: voice connection ended, reconnecting in %s", nudgeRetry)
+		}
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(nudgeRetry):
+		}
+	}
+}

cmd/mavwaked/nudge_test.go

@@ -0,0 +1,170 @@
+package main
+
+// The receiving half: a nudge pushed by mavend has to reach the speaker, and
+// it has to obey the same two gates a reply obeys (V-671).
+
+import (
+	"context"
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/kami/maven/internal/audio"
+	"github.com/kami/maven/internal/voice"
+)
+
+func nudgeAudio() audio.Audio {
+	return audio.Audio{Format: audio.PCM16kMono, Bytes: make([]byte, 8000)}
+}
+
+// pushFrame builds the frame mavend's voicesink sends.
+func pushFrame(t *testing.T, a audio.Audio) voice.Push {
+	t.Helper()
+	body, err := json.Marshal(voice.AudioNudgePush{
+		RuleName: "test-rule",
+		Severity: 3,
+		Audio:    a,
+		Text:     "пора пить воду",
+		Ts:       time.Unix(0, 0),
+	})
+	if err != nil {
+		t.Fatalf("marshal push: %v", err)
+	}
+	return voice.Push{Kind: voice.PushKindAudioNudge, Params: body}
+}
+
+// The defect itself: the push arrived and nothing came out of the speaker.
+func TestNudgeReachesThePlayer(t *testing.T) {
+	sess, p, snd := newTestSession(bargeInConfig{})
+	(&nudgeHandler{sess: sess}).OnPush(pushFrame(t, nudgeAudio()))
+
+	if p.plays != 0 {
+		t.Fatal("nudge played from the push goroutine; it must wait for the capture loop")
+	}
+	if err := sess.feed(context.Background(), silentBytes()); err != nil {
+		t.Fatalf("feed: %v", err)
+	}
+	if p.plays != 1 {
+		t.Fatalf("plays = %d, want 1", p.plays)
+	}
+	if len(p.last.Bytes) != 8000 {
+		t.Errorf("played %d bytes, want the nudge audio", len(p.last.Bytes))
+	}
+	if sess.nudges != 1 {
+		t.Errorf("nudges = %d, want 1", sess.nudges)
+	}
+	if len(snd.sent) != 0 {
+		t.Errorf("a nudge must not be shipped back to the daemon as an utterance")
+	}
+}
+
+// A push of some other kind, or one carrying no audio, must not reach the
+// player and must not wedge the one that follows.
+func TestNudgeIgnoresUnusablePushes(t *testing.T) {
+	sess, p, _ := newTestSession(bargeInConfig{})
+	h := &nudgeHandler{sess: sess}
+
+	h.OnPush(voice.Push{Kind: "something-else", Params: json.RawMessage(`{}`)})
+	h.OnPush(voice.Push{Kind: voice.PushKindAudioNudge, Params: json.RawMessage(`not json`)})
+	h.OnPush(pushFrame(t, audio.Audio{Format: audio.PCM16kMono}))
+
+	if err := sess.feed(context.Background(), silentBytes()); err != nil {
+		t.Fatalf("feed: %v", err)
+	}
+	if p.plays != 0 {
+		t.Fatalf("plays = %d, want 0", p.plays)
+	}
+
+	h.OnPush(pushFrame(t, nudgeAudio()))
+	if err := sess.feed(context.Background(), silentBytes()); err != nil {
+		t.Fatalf("feed: %v", err)
+	}
+	if p.plays != 1 {
+		t.Fatalf("plays after a usable nudge = %d, want 1", p.plays)
+	}
+}
+
+// The half-duplex gate covers a nudge exactly as it covers a reply: she does
+// not start one over herself, and the mic stays muted while it runs.
+func TestNudgeWaitsForTheReplyToFinish(t *testing.T) {
+	sess, p, _ := newTestSession(bargeInConfig{})
+	speakThenPause(t, sess)
+	if !p.Playing() {
+		t.Fatal("expected the reply to be playing")
+	}
+	plays := p.plays
+
+	(&nudgeHandler{sess: sess}).OnPush(pushFrame(t, nudgeAudio()))
+	for i := 0; i < 20; i++ {
+		if err := sess.feed(context.Background(), silentBytes()); err != nil {
+			t.Fatalf("feed: %v", err)
+		}
+	}
+	if p.plays != plays {
+		t.Fatalf("nudge cut across the reply: plays = %d, want %d", p.plays, plays)
+	}
+
+	p.playing = false
+	if err := sess.feed(context.Background(), silentBytes()); err != nil {
+		t.Fatalf("feed: %v", err)
+	}
+	if p.plays != plays+1 {
+		t.Fatalf("nudge never played after the reply ended: plays = %d", p.plays)
+	}
+}
+
+// Speaking a nudge must not leave half a sentence in the VAD. The frames
+// captured before it are pre-nudge speech, and splicing them onto whatever he
+// says afterwards ships one utterance that is two.
+func TestNudgeResetsTheVAD(t *testing.T) {
+	sess, p, snd := newTestSession(bargeInConfig{})
+	loud := frameAt(0.35)
+	speechFrames := (defaultSpeechMs + defaultFrameMs - 1) / defaultFrameMs
+	for i := 0; i < speechFrames+5; i++ {
+		if err := sess.feed(context.Background(), loud); err != nil {
+			t.Fatalf("feed: %v", err)
+		}
+	}
+
+	(&nudgeHandler{sess: sess}).OnPush(pushFrame(t, nudgeAudio()))
+	if err := sess.feed(context.Background(), silentBytes()); err != nil {
+		t.Fatalf("feed: %v", err)
+	}
+	if p.plays != 1 {
+		t.Fatalf("nudge did not play: plays = %d", p.plays)
+	}
+
+	// Playback ends, silence follows. The half-formed utterance must be gone
+	// rather than closing on the first quiet frame.
+	p.playing = false
+	silenceFrames := (defaultSilenceMs+defaultFrameMs-1)/defaultFrameMs + 2
+	for i := 0; i < silenceFrames; i++ {
+		if err := sess.feed(context.Background(), silentBytes()); err != nil {
+			t.Fatalf("feed: %v", err)
+		}
+	}
+	if len(snd.sent) != 0 {
+		t.Fatalf("sent %d utterances after a nudge, want 0", len(snd.sent))
+	}
+}
+
+// Two nudges queued back to back: the newer one is what he hears. The
+// PushHandler contract in internal/voice says the next nudge replaces the
+// stale one rather than dogpiling on it.
+func TestNudgeReplacesAnUnspokenOne(t *testing.T) {
+	sess, p, _ := newTestSession(bargeInConfig{})
+	h := &nudgeHandler{sess: sess}
+
+	h.OnPush(pushFrame(t, audio.Audio{Format: audio.PCM16kMono, Bytes: make([]byte, 4000)}))
+	h.OnPush(pushFrame(t, audio.Audio{Format: audio.PCM16kMono, Bytes: make([]byte, 12000)}))
+
+	if err := sess.feed(context.Background(), silentBytes()); err != nil {
+		t.Fatalf("feed: %v", err)
+	}
+	if p.plays != 1 {
+		t.Fatalf("plays = %d, want 1", p.plays)
+	}
+	if len(p.last.Bytes) != 12000 {
+		t.Errorf("played %d bytes, want the newer nudge", len(p.last.Bytes))
+	}
+}

cmd/mavwaked/session.go

@@ -7,6 +7,7 @@ package main
 import (
 	"context"
 	"log"
+	"sync"
 	"time"
 
 	"github.com/kami/maven/internal/audio"
@@ -19,6 +20,15 @@ type utteranceSender interface {
 	Send(ctx context.Context, utt audio.Audio, lang string) (audio.Audio, error)
 }
 
+// keywordGate answers whether the keyword has just been spoken. The
+// production one is wakeWord; tests substitute a recorder, because a gate that
+// can only be exercised with three ONNX files is a gate nobody tests.
+type keywordGate interface {
+	Feed(frame []int16) bool
+	Reset()
+	Score() float64
+}
+
 // bargeInConfig holds the two numbers barge-in needs. Zero Frames disables
 // barge-in entirely — the half-duplex gate still runs.
 type bargeInConfig struct {
@@ -62,11 +72,29 @@ type session struct {
 	// whenever playback ends.
 	loudFrames int
 
+	// wake is the keyword gate, or nil when no model was loaded. wakeUntil is
+	// how long a keyword stays good for: he says "Мэйвен" and then a sentence,
+	// and the VAD does not close the utterance until he stops, so the window
+	// has to outlive the word by the length of what follows it.
+	wake       keywordGate
+	wakeWindow time.Duration
+	wakeUntil  time.Time
+
+	// pending holds a nudge the push receiver handed over, waiting for the
+	// capture loop to speak it. It is the one field written from another
+	// goroutine, hence the mutex; everything else in this struct belongs to
+	// the capture loop alone.
+	nudgeMu sync.Mutex
+	pending *audio.Audio
+
 	// counters, read by tests and logged on the way out.
 	suppressed int // frames dropped because she was speaking
 	dropped    int // frames dropped as round-trip backlog
 	bargeIns   int // times playback was cut because he spoke over her
 	sent       int // utterances shipped to the daemon
+	nudges     int // proactive pushes spoken through the speaker
+	wakes      int // times the keyword opened the gate
+	ignored    int // complete utterances dropped because the keyword was absent
 
 	// loudSum and loudSeen accumulate the energy of suppressed frames, so
 	// the operator can read what the room actually measures and set
@@ -79,6 +107,12 @@ func newSession(vad *VAD, p player, s utteranceSender, lang string, barge bargeI
 	return &session{vad: vad, player: p, sender: s, lang: lang, barge: barge, now: time.Now}
 }
 
+// UseWakeWord puts the keyword gate in front of dispatch. Without it every
+// utterance is shipped, which is what mavwaked did before V-487 stage two.
+func (s *session) UseWakeWord(w keywordGate, window time.Duration) {
+	s.wake, s.wakeWindow = w, window
+}
+
 // frameDuration is the wall time one captured frame represents.
 const frameDuration = defaultFrameMs * time.Millisecond
 
@@ -138,6 +172,7 @@ func (s *session) feed(ctx context.Context, frame []byte) error {
 		s.bargeIns++
 		s.loudFrames = 0
 		s.vad.Reset()
+		s.resetWake()
 		log.Printf("mavwaked: barge-in — stopped playback")
 		s.replayRecent()
 		return nil
@@ -148,15 +183,101 @@ func (s *session) feed(ctx context.Context, frame []byte) error {
 	if s.loudFrames != 0 {
 		s.loudFrames = 0
 		s.vad.Reset()
+		// The wake word saw nothing during playback, so what it holds is from
+		// before she spoke. Judging what he says next on it would score a
+		// sentence that ended a reply ago.
+		s.resetWake()
 	}
 
-	utt, state := s.vad.Feed(PCMToI16(frame))
+	if s.startPendingNudge() {
+		return nil
+	}
+
+	// The keyword is scored on the same frames the VAD sees, and only on the
+	// ones that reach here: every path above returns while she is speaking, so
+	// her own voice saying "Мэйвен" cannot wake her.
+	pcm := PCMToI16(frame)
+	if s.wake != nil && s.wake.Feed(pcm) {
+		s.wakes++
+		s.wakeUntil = s.now().Add(s.wakeWindow)
+		log.Printf("mavwaked: keyword heard (score %.3f), listening for %s",
+			s.wake.Score(), s.wakeWindow)
+	}
+
+	utt, state := s.vad.Feed(pcm)
 	if state == StateSpeech || utt.Bytes == nil {
 		return nil
 	}
 	return s.dispatch(ctx, utt)
 }
 
+// Nudge hands proactive audio to the session, to be spoken as soon as the
+// capture loop finds a quiet moment. Safe to call from the push receiver
+// goroutine; nothing else here is.
+//
+// A nudge arriving while one is already waiting REPLACES it. That is the
+// contract internal/voice states for PushHandler: the next nudge replaces the
+// stale one in his attention rather than dogpiling on it.
+func (s *session) Nudge(a audio.Audio) {
+	if len(a.Bytes) == 0 {
+		return
+	}
+	s.nudgeMu.Lock()
+	if s.pending != nil {
+		log.Printf("mavwaked: nudge replaced one still waiting to be spoken")
+	}
+	s.pending = &a
+	s.nudgeMu.Unlock()
+}
+
+// takeNudge removes and returns the waiting nudge, or nil.
+func (s *session) takeNudge() *audio.Audio {
+	s.nudgeMu.Lock()
+	defer s.nudgeMu.Unlock()
+	a := s.pending
+	s.pending = nil
+	return a
+}
+
+// startPendingNudge speaks a waiting nudge and reports whether it started
+// one. It runs on the capture loop, past the half-duplex gate, so a nudge
+// never cuts across a reply and never plays into a backlog drain.
+//
+// The VAD is reset first. Playback is about to suppress every frame until it
+// ends, and a half-heard sentence left in the VAD would splice onto whatever
+// he says afterwards. Barge-in needs no special case: it reads the player,
+// and the player does not care which audio it is playing.
+func (s *session) startPendingNudge() bool {
+	a := s.takeNudge()
+	if a == nil {
+		return false
+	}
+	s.vad.Reset()
+	s.nudges++
+	log.Printf("mavwaked: speaking nudge (%.2fs audio)", a.Duration())
+	s.player.Play(*a)
+	return true
+}
+
+// awake reports whether an utterance ending now was addressed to her.
+//
+// With no wake word loaded every utterance is, which is exactly what mavwaked
+// did before this gate existed. An operator with no model file gets the old
+// daemon rather than a daemon that refuses to hear anything.
+func (s *session) awake() bool {
+	if s.wake == nil {
+		return true
+	}
+	return s.now().Before(s.wakeUntil)
+}
+
+// resetWake drops the gate's streaming state when there is a gate.
+func (s *session) resetWake() {
+	if s.wake != nil {
+		s.wake.Reset()
+	}
+}
+
 // keepRecent stores a copy of one barge-in trigger frame, keeping at most
 // barge.Frames of them.
 func (s *session) keepRecent(frame []byte) {
@@ -197,6 +318,19 @@ func (s *session) replayRecent() {
 // whole backlog straight into the VAD, and a Send error did the same on every
 // failed turn, so a dead socket drove a retry loop off nothing but backlog.
 func (s *session) dispatch(ctx context.Context, utt audio.Audio) error {
+	if !s.awake() {
+		s.ignored++
+		log.Printf("mavwaked: utterance ignored, keyword not heard (%.2fs, %d ignored so far)",
+			utt.Duration(), s.ignored)
+		s.vad.Reset()
+		s.resetWake()
+		return nil
+	}
+	// One keyword, one turn. A window that renewed itself on every reply would
+	// leave the microphone open for as long as he kept talking, which is the
+	// state this gate exists to end.
+	s.wakeUntil = time.Time{}
+
 	log.Printf("mavwaked: utterance complete (%.2fs, %d bytes), sending...", utt.Duration(), len(utt.Bytes))
 	start := s.now()
 	reply, err := s.sender.Send(ctx, utt, s.lang)
@@ -225,6 +359,7 @@ func (s *session) dispatch(ctx context.Context, utt audio.Audio) error {
 // recorded before she started speaking.
 func (s *session) dropBacklog(start time.Time) {
 	s.vad.Reset()
+	s.resetWake()
 	s.loudFrames = 0
 	s.recent = s.recent[:0]
 	if elapsed := s.now().Sub(start); elapsed > 0 {

cmd/mavwaked/wakefeatures.go

@@ -0,0 +1,187 @@
+package main
+
+// The three models behind the wake word (V-487 stage two).
+//
+// openWakeWord's pipeline, run in a row:
+//
+//	audio      -> melspectrogram.onnx -> 32-bin mel frames, one per 10ms
+//	76 frames  -> embedding_model.onnx -> one 96-dim embedding per 80ms
+//	16 embeds  -> maven_wakeword.onnx  -> one score
+//
+// The first two are frozen and pretrained. Only the last was trained here,
+// which is why it is 100KB and the other two are megabytes. The shapes are
+// not guesses: 2.0s of 16kHz audio measures 197 mel frames, and 76-frame
+// windows at stride 8 give exactly the 16 embeddings the head was fitted on.
+//
+// This file knows ONNX and nothing about the 80ms cadence. wakeword.go knows
+// the cadence and nothing about tensors.
+
+import (
+	"fmt"
+
+	ort "github.com/yalue/onnxruntime_go"
+)
+
+const (
+	// melHop — samples per mel frame. 10ms at 16kHz.
+	melHop = 160
+	// melBins — mel bins per frame, fixed by melspectrogram.onnx.
+	melBins = 32
+	// embedFrames — mel frames one embedding is computed over, 760ms.
+	embedFrames = 76
+	// embedStride — mel frames between embeddings, 80ms.
+	embedStride = 8
+	// embedDim — the embedding width.
+	embedDim = 96
+	// headWindow — embeddings the head scores at once, 1.28s of audio.
+	headWindow = 16
+
+	// melContext — samples of history prepended to each incremental mel
+	// call, chosen so the eight frames this call yields continue exactly
+	// where the previous call's eight stopped.
+	//
+	// melspectrogram.onnx returns N/160-3 frames for N samples, and frame i
+	// covers [i*160, i*160+400). With 480 samples of history the buffer is
+	// 1760 samples, which is 8 frames, and the oldest of them starts one hop
+	// after the newest of the previous call. Less history leaves a gap: the
+	// first frames of a bare chunk would be computed against silence.
+	melContext = 480
+
+	// chunkSamples — audio per embedding step, 80ms.
+	chunkSamples = embedStride * melHop
+)
+
+// wakeModels holds the three ONNX sessions. It runs on CPU threads beside
+// silero and never touches the GPU. That is a rule, not a result: a wake word
+// that waits on card admission is not a wake word.
+type wakeModels struct {
+	mel  *ort.DynamicAdvancedSession
+	emb  *ort.DynamicAdvancedSession
+	head *ort.DynamicAdvancedSession
+}
+
+// newWakeModels loads all three. melPath and embedPath are openWakeWord's
+// frozen feature models; headPath is the keyword head trained for "Мэйвен".
+func newWakeModels(melPath, embedPath, headPath, libPath string) (*wakeModels, error) {
+	if !ort.IsInitialized() {
+		if libPath != "" {
+			ort.SetSharedLibraryPath(libPath)
+		}
+		if err := ort.InitializeEnvironment(); err != nil {
+			return nil, fmt.Errorf("wake word: onnx runtime: %w", err)
+		}
+	}
+	open := func(p string, in, out []string) (*ort.DynamicAdvancedSession, error) {
+		s, err := ort.NewDynamicAdvancedSession(p, in, out, nil)
+		if err != nil {
+			return nil, fmt.Errorf("wake word: load %s: %w", p, err)
+		}
+		return s, nil
+	}
+	m := &wakeModels{}
+	var err error
+	if m.mel, err = open(melPath, []string{"input"}, []string{"output"}); err != nil {
+		return nil, err
+	}
+	if m.emb, err = open(embedPath, []string{"input_1"}, []string{"conv2d_19"}); err != nil {
+		m.Close()
+		return nil, err
+	}
+	if m.head, err = open(headPath, []string{"embeddings"}, []string{"score"}); err != nil {
+		m.Close()
+		return nil, err
+	}
+	return m, nil
+}
+
+// Close releases the three sessions.
+func (m *wakeModels) Close() {
+	if m == nil {
+		return
+	}
+	for _, s := range []*ort.DynamicAdvancedSession{m.mel, m.emb, m.head} {
+		if s != nil {
+			s.Destroy()
+		}
+	}
+	m.mel, m.emb, m.head = nil, nil, nil
+}
+
+// melFrames runs one buffer of samples and returns the mel frames it yielded.
+func (m *wakeModels) melFrames(buf []float32) ([][melBins]float32, error) {
+	in, err := ort.NewTensor(ort.NewShape(1, int64(len(buf))), buf)
+	if err != nil {
+		return nil, err
+	}
+	defer in.Destroy()
+
+	n := int64(len(buf)/melHop - 3)
+	if n < 1 {
+		return nil, fmt.Errorf("wake word: %d samples yield no mel frames", len(buf))
+	}
+	out, err := ort.NewEmptyTensor[float32](ort.NewShape(1, 1, n, melBins))
+	if err != nil {
+		return nil, err
+	}
+	defer out.Destroy()
+
+	if err := m.mel.Run([]ort.Value{in}, []ort.Value{out}); err != nil {
+		return nil, err
+	}
+	data := out.GetData()
+	frames := make([][melBins]float32, n)
+	for i := range frames {
+		for j := 0; j < melBins; j++ {
+			// The scaling openWakeWord applies between the two feature
+			// models, and the head was fitted on its output.
+			frames[i][j] = data[i*melBins+j]/10.0 + 2.0
+		}
+	}
+	return frames, nil
+}
+
+// embedding runs embedFrames mel frames through the frozen embedder.
+func (m *wakeModels) embedding(mels [][melBins]float32) ([embedDim]float32, error) {
+	var e [embedDim]float32
+	flat := make([]float32, 0, embedFrames*melBins)
+	for _, f := range mels {
+		flat = append(flat, f[:]...)
+	}
+	in, err := ort.NewTensor(ort.NewShape(1, embedFrames, melBins, 1), flat)
+	if err != nil {
+		return e, err
+	}
+	defer in.Destroy()
+	out, err := ort.NewEmptyTensor[float32](ort.NewShape(1, 1, 1, embedDim))
+	if err != nil {
+		return e, err
+	}
+	defer out.Destroy()
+	if err := m.emb.Run([]ort.Value{in}, []ort.Value{out}); err != nil {
+		return e, err
+	}
+	copy(e[:], out.GetData())
+	return e, nil
+}
+
+// score runs the trained head over headWindow embeddings.
+func (m *wakeModels) score(embeds [][embedDim]float32) (float64, error) {
+	flat := make([]float32, 0, headWindow*embedDim)
+	for _, e := range embeds {
+		flat = append(flat, e[:]...)
+	}
+	in, err := ort.NewTensor(ort.NewShape(1, headWindow, embedDim), flat)
+	if err != nil {
+		return 0, err
+	}
+	defer in.Destroy()
+	out, err := ort.NewEmptyTensor[float32](ort.NewShape(1, 1))
+	if err != nil {
+		return 0, err
+	}
+	defer out.Destroy()
+	if err := m.head.Run([]ort.Value{in}, []ort.Value{out}); err != nil {
+		return 0, err
+	}
+	return float64(out.GetData()[0]), nil
+}

cmd/mavwaked/wakeword.go

@@ -0,0 +1,191 @@
+package main
+
+// The wake word, "Мэйвен" (V-487 stage two).
+//
+// Silero answers "is this frame speech". It does not answer "was this said to
+// her", and until this file existed nothing did: every utterance near the
+// microphone became a turn. What made that safe rather than expensive was
+// SurfaceVoice capping acts at L0, and L0 does not cap reading, so the room
+// could still hear his facts read back.
+//
+// This file owns the 80ms cadence and the three rings of state between the
+// models. wakefeatures.go owns the tensors.
+//
+// Nil is a working value, and it is the CLOSED gate rather than the open one.
+// Feed on a nil receiver reports no keyword; session.go asks separately
+// whether a gate exists at all. That split is deliberate: a nil that answers
+// "yes, keyword" reads as a working wake word in every log line it produces.
+
+import (
+	"log"
+	"sync"
+)
+
+// defaultWakeThreshold — score above which the keyword was said. Picked from
+// the false-accept rate on held-out Russian speech, not from accuracy: a miss
+// costs him a repeat, a false accept costs a turn nobody asked for. See
+// docs/evals for the wakes-per-hour this buys.
+const defaultWakeThreshold = 0.99
+
+// wakeWord is the streaming state around wakeModels. It is fed the same
+// capture frames the VAD sees and answers whether the keyword has just been
+// spoken.
+type wakeWord struct {
+	mu sync.Mutex
+	m  *wakeModels
+
+	threshold float64
+
+	// pending holds captured samples not yet part of a full 80ms chunk, and
+	// history holds the melContext samples before them.
+	pending []float32
+	history []float32
+
+	// mels is the newest embedFrames mel frames, oldest first.
+	mels [][melBins]float32
+	// embeds is the newest headWindow embeddings, oldest first.
+	embeds [][embedDim]float32
+
+	last float64 // most recent score, held between chunks
+}
+
+// newWakeWord loads the models and wraps them in the streaming gate.
+func newWakeWord(melPath, embedPath, headPath, libPath string, threshold float64) (*wakeWord, error) {
+	m, err := newWakeModels(melPath, embedPath, headPath, libPath)
+	if err != nil {
+		return nil, err
+	}
+	if threshold <= 0 {
+		threshold = defaultWakeThreshold
+	}
+	return &wakeWord{m: m, threshold: threshold}, nil
+}
+
+// Close releases the models.
+func (w *wakeWord) Close() {
+	if w == nil {
+		return
+	}
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	w.m.Close()
+	w.m = nil
+}
+
+// Feed takes one capture frame and reports whether the keyword was heard on
+// it. A nil wakeWord hears nothing.
+func (w *wakeWord) Feed(frame []int16) bool {
+	if w == nil {
+		return false
+	}
+	w.mu.Lock()
+	defer w.mu.Unlock()
+
+	for _, v := range frame {
+		w.pending = append(w.pending, float32(v)/32768.0)
+	}
+	fired := false
+	for len(w.pending) >= chunkSamples {
+		chunk := w.pending[:chunkSamples]
+		if w.step(chunk) {
+			fired = true
+		}
+		w.history = append(w.history[:0], tailFloat32(append(w.history, chunk...), melContext)...)
+		// Slide the remainder to the front rather than reslicing. This runs
+		// every 80ms for as long as the daemon lives.
+		w.pending = append(w.pending[:0], w.pending[chunkSamples:]...)
+	}
+	return fired
+}
+
+// Reset drops the streaming state, so a fresh utterance is not judged on audio
+// from before it. Called after every dispatch and after barge-in, for the same
+// reason silero is: echo-era history must not score the next sentence, and her
+// own voice saying the keyword must not wake her.
+func (w *wakeWord) Reset() {
+	if w == nil {
+		return
+	}
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	w.pending, w.history = w.pending[:0], w.history[:0]
+	w.mels, w.embeds = nil, nil
+	w.last = 0
+}
+
+// Score returns the most recent score, for the operator to read out of the
+// journal when picking a threshold for his room.
+func (w *wakeWord) Score() float64 {
+	if w == nil {
+		return 0
+	}
+	w.mu.Lock()
+	defer w.mu.Unlock()
+	return w.last
+}
+
+// step runs one 80ms chunk through all three models. It returns true when the
+// score crosses the threshold on this chunk.
+func (w *wakeWord) step(chunk []float32) bool {
+	buf := make([]float32, 0, melContext+len(chunk))
+	if pad := melContext - len(w.history); pad > 0 {
+		buf = append(buf, make([]float32, pad)...)
+	}
+	buf = append(buf, tailFloat32(w.history, melContext)...)
+	buf = append(buf, chunk...)
+
+	frames, err := w.m.melFrames(buf)
+	if err != nil {
+		// A failed inference must not silence the microphone. Hold the last
+		// score and let the next chunk try again.
+		log.Printf("mavwaked: wake word: mel: %v", err)
+		return false
+	}
+	w.mels = tailMel(append(w.mels, frames...), embedFrames)
+	if len(w.mels) < embedFrames {
+		return false
+	}
+	e, err := w.m.embedding(w.mels)
+	if err != nil {
+		log.Printf("mavwaked: wake word: embedding: %v", err)
+		return false
+	}
+	w.embeds = tailEmbed(append(w.embeds, e), headWindow)
+	if len(w.embeds) < headWindow {
+		return false
+	}
+	score, err := w.m.score(w.embeds)
+	if err != nil {
+		log.Printf("mavwaked: wake word: head: %v", err)
+		return false
+	}
+	// Report the crossing, not the state. A keyword held above the threshold
+	// for a second is one wake, and firing on every chunk of it would make the
+	// gate look open when it is merely slow to fall.
+	crossed := score >= w.threshold && w.last < w.threshold
+	w.last = score
+	return crossed
+}
+
+// The three rings. Each keeps the newest n entries and nothing older.
+
+func tailFloat32(s []float32, n int) []float32 {
+	if len(s) <= n {
+		return s
+	}
+	return s[len(s)-n:]
+}
+
+func tailMel(s [][melBins]float32, n int) [][melBins]float32 {
+	if len(s) <= n {
+		return s
+	}
+	return append(s[:0], s[len(s)-n:]...)
+}
+
+func tailEmbed(s [][embedDim]float32, n int) [][embedDim]float32 {
+	if len(s) <= n {
+		return s
+	}
+	return append(s[:0], s[len(s)-n:]...)
+}

cmd/mavwaked/wakeword_test.go

@@ -0,0 +1,174 @@
+package main
+
+import (
+	"context"
+	"testing"
+	"time"
+)
+
+// fakeGate fires on demand instead of running three ONNX models. The gate's
+// own arithmetic is measured on real audio in docs/evals; what these tests
+// cover is the thing that decides whether an utterance is shipped.
+type fakeGate struct {
+	fireOn int // fire when this many frames have been fed, 0 never fires
+	fed    int
+	resets int
+}
+
+func (g *fakeGate) Feed(_ []int16) bool {
+	g.fed++
+	return g.fireOn > 0 && g.fed == g.fireOn
+}
+func (g *fakeGate) Reset()         { g.resets++ }
+func (g *fakeGate) Score() float64 { return 1 }
+
+// wakingSession wires a session whose gate fires on the first frame it sees.
+func wakingSession(fireOn int, window time.Duration) (*session, *fakePlayer, *fakeSender, *fakeGate) {
+	sess, p, snd := newTestSession(bargeInConfig{})
+	g := &fakeGate{fireOn: fireOn}
+	sess.UseWakeWord(g, window)
+	return sess, p, snd, g
+}
+
+func TestKeywordlessSpeechNeverReachesSTT(t *testing.T) {
+	sess, p, snd, g := wakingSession(0, 8*time.Second)
+	speakThenPause(t, sess)
+
+	if len(snd.sent) != 0 {
+		t.Fatalf("sent %d utterances, want 0 — this is the whole point of V-487", len(snd.sent))
+	}
+	if sess.ignored != 1 {
+		t.Errorf("ignored = %d, want 1", sess.ignored)
+	}
+	if p.plays != 0 {
+		t.Errorf("plays = %d, want 0", p.plays)
+	}
+	if g.fed == 0 {
+		t.Error("the gate was never fed a frame")
+	}
+}
+
+func TestKeywordOpensTheGate(t *testing.T) {
+	sess, p, snd, _ := wakingSession(1, 8*time.Second)
+	speakThenPause(t, sess)
+
+	if len(snd.sent) != 1 {
+		t.Fatalf("sent %d utterances, want 1", len(snd.sent))
+	}
+	if sess.wakes != 1 {
+		t.Errorf("wakes = %d, want 1", sess.wakes)
+	}
+	if sess.ignored != 0 {
+		t.Errorf("ignored = %d, want 0", sess.ignored)
+	}
+	if p.plays != 1 {
+		t.Errorf("plays = %d, want 1", p.plays)
+	}
+}
+
+// One keyword buys one turn. Without this the microphone stays open for as
+// long as he keeps talking, which is the state the gate exists to end.
+func TestOneKeywordBuysOneTurn(t *testing.T) {
+	sess, p, snd, _ := wakingSession(1, 8*time.Second)
+	speakThenPause(t, sess)
+	p.Stop()         // she finished her reply
+	sess.discard = 0 // the backlog drain is not what this measures
+	speakThenPause(t, sess)
+
+	if len(snd.sent) != 1 {
+		t.Fatalf("sent %d utterances, want 1: the second had no keyword", len(snd.sent))
+	}
+	if sess.ignored != 1 {
+		t.Errorf("ignored = %d, want 1", sess.ignored)
+	}
+}
+
+// The keyword is heard, then he says nothing for longer than the window. What
+// he says after that is not addressed to her.
+func TestTheKeywordExpires(t *testing.T) {
+	sess, _, snd, _ := wakingSession(1, 500*time.Millisecond)
+	now := time.Unix(1750000000, 0)
+	sess.now = func() time.Time { return now }
+
+	if err := sess.feed(context.Background(), silentBytes()); err != nil {
+		t.Fatalf("feed: %v", err)
+	}
+	if sess.wakes != 1 {
+		t.Fatalf("wakes = %d, want 1", sess.wakes)
+	}
+	now = now.Add(2 * time.Second)
+	speakThenPause(t, sess)
+
+	if len(snd.sent) != 0 {
+		t.Fatalf("sent %d utterances, want 0 — the keyword had expired", len(snd.sent))
+	}
+}
+
+// Barge-in cuts her off whether or not the keyword was heard. What he says
+// after cutting her off still has to carry it.
+func TestBargeInStillInterruptsHer(t *testing.T) {
+	sess, p, _, g := wakingSession(0, 8*time.Second)
+	sess.barge = bargeInConfig{RMS: 0.2, Frames: 3}
+	p.playing = true
+	loud := frameAt(0.35)
+	for i := 0; i < 4; i++ {
+		if err := sess.feed(context.Background(), loud); err != nil {
+			t.Fatalf("feed %d: %v", i, err)
+		}
+	}
+	if sess.bargeIns != 1 {
+		t.Fatalf("bargeIns = %d, want 1", sess.bargeIns)
+	}
+	if p.stops != 1 {
+		t.Errorf("stops = %d, want 1", p.stops)
+	}
+	if g.resets == 0 {
+		t.Error("barge-in left pre-playback audio in the gate")
+	}
+}
+
+// Her own reply must not wake her. Frames captured while the player runs never
+// reach the gate, and the gate is cleared when playback ends.
+func TestHerOwnVoiceNeverReachesTheGate(t *testing.T) {
+	sess, p, _, g := wakingSession(1, 8*time.Second)
+	p.playing = true
+	for i := 0; i < 10; i++ {
+		if err := sess.feed(context.Background(), frameAt(0.35)); err != nil {
+			t.Fatalf("feed: %v", err)
+		}
+	}
+	if g.fed != 0 {
+		t.Fatalf("gate was fed %d frames while she was speaking, want 0", g.fed)
+	}
+	if sess.wakes != 0 {
+		t.Errorf("wakes = %d, want 0", sess.wakes)
+	}
+}
+
+// No model, no gate: the daemon behaves exactly as it did before V-487 stage
+// two. An operator with a missing file gets yesterday's mavwaked, not one that
+// refuses to hear anything.
+func TestNoGateShipsEveryUtterance(t *testing.T) {
+	sess, _, snd := newTestSession(bargeInConfig{})
+	speakThenPause(t, sess)
+
+	if len(snd.sent) != 1 {
+		t.Fatalf("sent %d utterances, want 1", len(snd.sent))
+	}
+	if sess.ignored != 0 {
+		t.Errorf("ignored = %d, want 0", sess.ignored)
+	}
+}
+
+// A nil *wakeWord is the closed gate, not a crash and not an open one.
+func TestNilWakeWordHearsNothing(t *testing.T) {
+	var w *wakeWord
+	if w.Feed([]int16{0, 0, 0}) {
+		t.Error("a nil wake word reported the keyword")
+	}
+	if w.Score() != 0 {
+		t.Error("a nil wake word reported a score")
+	}
+	w.Reset()
+	w.Close()
+}

docs/deployment.md

@@ -170,9 +170,13 @@ The device is `plughw:0,0` and not `hw:0,0`. The fifine offers 2 channels at
 44100 or 48000 and nothing else, and mavwaked asks arecord for 16kHz mono. Bare
 `hw` dies on "Channels count non available" before a frame is read.
 
-There is no wake word yet (V-487 stage two), so the loop runs open. mavwaked
-connects lazily, so `voicesink` cannot push a nudge to it until it has sent one
-utterance.
+There is no wake word yet (V-487 stage two), so the loop runs open.
+
+mavwaked connects at startup and holds the conn, so a nudge routed to voice
+reaches the speaker before he has said anything (V-671). It used to connect
+lazily, which made the failure silent rather than absent: after one utterance
+the session existed, `PushToMostRecent` succeeded, the dispatcher stopped
+rerouting to telegram and ntfy, and mavwaked discarded the audio.
 
 **Passwords are read from files, never taken as flag values.** `mavcaldav` uses
 `-pass-file` and `-render-pass-file`. `mavpoll` and `mavmaild` follow the same

internal/voice/client.go

@@ -9,15 +9,18 @@
 //
 // The wire is symmetric: a Request from the client is answered by a
 // Response with a matching ID, OR a server-initiated Push frame (no ID)
-// may arrive interleaved. SendRequest loops reading frames, drops Push
-// frames to the harness if a receiver is running (or silently if not),
-// and returns the first Response with the matching ID.
+// may arrive interleaved. One reader goroutine per connection owns the
+// socket. It hands each Response to whichever SendRequest is waiting on
+// that ID and each Push to the handler, so a client may send and listen
+// at the same time on one conn. mavwaked needs exactly that: it speaks
+// utterances and it must hear nudges, and the server routes a nudge to
+// the session that spoke most recently, so a second listening conn would
+// never be picked (V-671).
 package voice
 
 import (
 	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"io"
 	"net"
@@ -41,13 +44,22 @@ type PushHandler interface {
 // Client — one connection to the voice.Server.
 type Client struct {
 	addr   string
-	mu     sync.Mutex
-	c      net.Conn
 	nextID atomic.Uint64
 
-	// pushCh fan-out: a reader goroutine (started by RunPushReceiver)
-	// writes Push frames here; SendRequest also drains it when no reader
-	// is running (drops the frame in that case).
+	mu sync.Mutex
+	c  net.Conn
+	// pending holds one channel per in-flight request, keyed by frame id.
+	// The reader goroutine delivers the Response here and deletes the entry.
+	pending map[uint64]chan *Response
+	// dead is closed by the reader goroutine when this conn ends, so a
+	// waiting SendRequest fails at once instead of at its own deadline.
+	dead chan struct{}
+
+	// wmu serialises writes. Frames must not interleave on the wire.
+	wmu sync.Mutex
+
+	// pushH is set by RunPushReceiver and survives a reconnect, because the
+	// client that wants pushes wants them on whatever conn it ends up with.
 	pushMu sync.Mutex
 	pushH  PushHandler
 }
@@ -55,6 +67,15 @@ type Client struct {
 // Dial returns a Client that will connect to addr on first use.
 func Dial(addr string) *Client { return &Client{addr: addr} }
 
+// Connect opens the conn now rather than on the first request. mavwaked calls
+// it at startup: the server registers a session on accept, and a client that
+// has never connected cannot be sent a nudge.
+func (c *Client) Connect(ctx context.Context) error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.ensureConnLocked(ctx)
+}
+
 // Close releases the conn. Idempotent.
 func (c *Client) Close() error {
 	c.mu.Lock()
@@ -75,12 +96,14 @@ func (c *Client) PushToTalk(ctx context.Context, a audio.Audio, lang string) (Pu
 	return out, err
 }
 
+// requestTimeout bounds a round-trip with no deadline on its context. It is
+// generous because the far end runs speech-to-text, a router and a voice.
+const requestTimeout = 120 * time.Second
+
 // SendRequest sends one Request frame and waits for the matching Response.
-// Push frames received while waiting are dropped on the floor UNLESS a
-// PushHandler has been wired via RunPushReceiver, in which case the handler
-// is invoked inline (still synchronous with the SendRequest caller's
-// read). For sanity, the reference client runs either one-shot (no
-// receiver) or interactive (RunPushReceiver, no concurrent SendRequest).
+// Push frames arriving meanwhile go to the handler on the reader goroutine,
+// so listening and sending on one Client is supported rather than merely
+// tolerated.
 func (c *Client) SendRequest(ctx context.Context, m Method, params any, out any) error {
 	body, err := marshalParams(params)
 	if err != nil {
@@ -94,58 +117,69 @@ func (c *Client) SendRequest(ctx context.Context, m Method, params any, out any)
 		c.mu.Unlock()
 		return err
 	}
-	conn := c.c
+	conn, dead := c.c, c.dead
+	ch := make(chan *Response, 1)
+	c.pending[id] = ch
 	c.mu.Unlock()
 
-	if dl, ok := ctx.Deadline(); ok {
-		_ = conn.SetDeadline(dl)
-	} else {
-		_ = conn.SetDeadline(time.Now().Add(120 * time.Second))
-	}
-	defer conn.SetDeadline(time.Time{})
-
-	if err := writeFrame(conn, &req); err != nil {
-		c.teardown()
+	c.wmu.Lock()
+	err = writeFrame(conn, &req)
+	c.wmu.Unlock()
+	if err != nil {
+		c.forget(id)
+		c.teardownConn(conn)
 		return err
 	}
-	for {
-		resp, push, err := readOneFrame(conn)
-		if err != nil {
-			c.teardown()
-			return err
-		}
-		if push != nil {
-			c.deliverPush(*push)
-			continue
-		}
-		if resp.ID != id {
-			continue // not ours; ignore (singleplex ⇒ shouldn't happen)
-		}
-		if resp.Error != nil {
-			return hydrate(resp.Error)
-		}
-		if out != nil {
-			if err := json.Unmarshal(resp.Result, out); err != nil {
-				return fmt.Errorf("voice: unmarshal result: %w", err)
-			}
-		}
-		return nil
+
+	timer := time.NewTimer(requestTimeout)
+	defer timer.Stop()
+
+	var resp *Response
+	select {
+	case resp = <-ch:
+	case <-dead:
+		c.forget(id)
+		return fmt.Errorf("voice: connection closed before reply")
+	case <-ctx.Done():
+		c.forget(id)
+		return ctx.Err()
+	case <-timer.C:
+		c.forget(id)
+		c.teardownConn(conn)
+		return fmt.Errorf("voice: no reply within %s", requestTimeout)
 	}
+
+	if resp.Error != nil {
+		return hydrate(resp.Error)
+	}
+	if out != nil {
+		if err := json.Unmarshal(resp.Result, out); err != nil {
+			return fmt.Errorf("voice: unmarshal result: %w", err)
+		}
+	}
+	return nil
 }
 
-// RunPushReceiver spawns a reader goroutine that delivers Push frames to h
-// until the conn closes or Close is called. Today's reference client uses
-// this in -listen mode (proactive voice playback). SendRequest and
-// RunPushReceiver SHOULD NOT be used concurrently on the same Client — the
-// wire is singleplex at the reference client's scale; production picks one
-// mode per conn. Returns when the goroutine ends (ctx cancel or conn close).
+// forget drops an abandoned request so a late Response is discarded rather
+// than delivered to nobody.
+func (c *Client) forget(id uint64) {
+	c.mu.Lock()
+	delete(c.pending, id)
+	c.mu.Unlock()
+}
+
+// RunPushReceiver wires h and blocks until the conn ends or ctx is
+// cancelled. Frames are read by the per-conn reader goroutine, so a client
+// may call SendRequest on the same Client while this is running. Returns nil
+// when the conn ended, so a caller that wants to stay reachable reconnects
+// and calls it again.
 func (c *Client) RunPushReceiver(ctx context.Context, h PushHandler) error {
 	c.mu.Lock()
 	if err := c.ensureConnLocked(ctx); err != nil {
 		c.mu.Unlock()
 		return err
 	}
-	conn := c.c
+	dead := c.dead
 	c.mu.Unlock()
 
 	c.pushMu.Lock()
@@ -158,21 +192,34 @@ func (c *Client) RunPushReceiver(ctx context.Context, h PushHandler) error {
 		c.pushMu.Unlock()
 	}()
 
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-dead:
+		return nil
+	}
+}
+
+// readLoop owns conn for its whole life. It ends on any read error, which is
+// how a closed conn, a killed server and a cancelled dial all arrive here.
+func (c *Client) readLoop(conn net.Conn, dead chan struct{}) {
+	defer close(dead)
 	for {
-		select {
-		case <-ctx.Done():
-			return ctx.Err()
-		default:
-		}
-		_, push, err := readOneFrame(conn)
+		resp, push, err := readOneFrame(conn)
 		if err != nil {
-			if errors.Is(err, io.EOF) || errors.Is(err, net.ErrClosed) {
-				return nil
-			}
-			return err
+			c.teardownConn(conn)
+			return
 		}
 		if push != nil {
 			c.deliverPush(*push)
+			continue
+		}
+		c.mu.Lock()
+		ch := c.pending[resp.ID]
+		delete(c.pending, resp.ID)
+		c.mu.Unlock()
+		if ch != nil {
+			ch <- resp
 		}
 	}
 }
@@ -196,13 +243,19 @@ func (c *Client) ensureConnLocked(ctx context.Context) error {
 		return fmt.Errorf("voice: dial %s: %w", c.addr, err)
 	}
 	c.c = conn
+	c.pending = make(map[uint64]chan *Response)
+	c.dead = make(chan struct{})
+	go c.readLoop(conn, c.dead)
 	return nil
 }
 
-func (c *Client) teardown() {
+// teardownConn closes conn and forgets it, but only if it is still the live
+// one. A reconnect may already have replaced it, and closing the new conn
+// because the old one died takes the client down on every hiccup.
+func (c *Client) teardownConn(conn net.Conn) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	if c.c != nil {
+	if c.c != nil && c.c == conn {
 		_ = c.c.Close()
 		c.c = nil
 	}

internal/voice/voice_test.go

@@ -221,3 +221,113 @@ func TestClientListenModeReceivesPush(t *testing.T) {
 type pushHandlerFunc func(Push)
 
 func (f pushHandlerFunc) OnPush(p Push) { f(p) }
+
+// The whole point of the per-conn reader (V-671): mavwaked speaks utterances
+// and must hear nudges, and the server routes a nudge to the session that
+// spoke most recently. A second listening conn would never be picked, so both
+// directions have to share one conn.
+func TestClientSendsAndListensOnOneConn(t *testing.T) {
+	l := newTestListener(t)
+	sess := NewSessions()
+	h := &stubHandler{}
+	srv := NewServer(l.Addr().String(), h, sess)
+	if err := srv.Listen(); err != nil {
+		t.Fatalf("listen: %v", err)
+	}
+	defer func() {
+		_ = srv.Close()
+		waitPort()
+	}()
+	go func() { _ = srv.Serve() }()
+
+	c := Dial(l.Addr().String())
+	defer c.Close()
+
+	got := make(chan audio.Audio, 4)
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		_ = c.RunPushReceiver(ctx, pushHandlerFunc(func(p Push) {
+			var ap AudioNudgePush
+			if err := json.Unmarshal(p.Params, &ap); err == nil {
+				got <- ap.Audio
+			}
+		}))
+	}()
+
+	for i := 0; i < 100 && sess.Active() < 1; i++ {
+		time.Sleep(10 * time.Millisecond)
+	}
+	if sess.Active() != 1 {
+		t.Fatalf("active sessions = %d, want exactly 1", sess.Active())
+	}
+
+	// A round-trip while the receiver is running. Before the reader owned the
+	// conn, this and the receiver raced for every frame.
+	resp, err := c.PushToTalk(context.Background(), audio.Audio{Format: audio.PCM16kMono, Bytes: []byte("hello")}, "ru")
+	if err != nil {
+		t.Fatalf("PushToTalk with a receiver running: %v", err)
+	}
+	if resp.ReplyText != "got it" {
+		t.Fatalf("ReplyText = %q, want %q", resp.ReplyText, "got it")
+	}
+
+	// And the nudge still arrives, on the session that just spoke.
+	err = sess.PushToMostRecent(context.Background(), AudioNudgePush{
+		RuleName: "after-speaking",
+		Audio:    audio.Audio{Format: audio.PCM16kMono, Bytes: []byte("proactive")},
+	})
+	if err != nil {
+		t.Fatalf("PushToMostRecent: %v", err)
+	}
+	select {
+	case a := <-got:
+		if string(a.Bytes) != "proactive" {
+			t.Fatalf("received %q, want the nudge audio", string(a.Bytes))
+		}
+	case <-time.After(2 * time.Second):
+		t.Fatal("nudge never reached the handler after the client had spoken")
+	}
+}
+
+// A request abandoned by its context must not leave its slot behind, or a
+// long-running client leaks one channel per timeout.
+func TestClientForgetsAbandonedRequests(t *testing.T) {
+	l := newTestListener(t)
+	sess := NewSessions()
+	srv := NewServer(l.Addr().String(), &blockingHandler{}, sess)
+	if err := srv.Listen(); err != nil {
+		t.Fatalf("listen: %v", err)
+	}
+	defer func() {
+		_ = srv.Close()
+		waitPort()
+	}()
+	go func() { _ = srv.Serve() }()
+
+	c := Dial(l.Addr().String())
+	defer c.Close()
+
+	ctx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
+	defer cancel()
+	_, err := c.PushToTalk(ctx, audio.Audio{Format: audio.PCM16kMono, Bytes: []byte("x")}, "ru")
+	if err == nil {
+		t.Fatal("expected the round-trip to fail on its context")
+	}
+
+	c.mu.Lock()
+	n := len(c.pending)
+	c.mu.Unlock()
+	if n != 0 {
+		t.Fatalf("pending = %d after an abandoned request, want 0", n)
+	}
+}
+
+// blockingHandler never answers, so the client's context is what ends the
+// round-trip.
+type blockingHandler struct{}
+
+func (blockingHandler) HandlePushToTalk(ctx context.Context, _ PushToTalkReq, _ uint64) (PushToTalkResp, error) {
+	<-ctx.Done()
+	return PushToTalkResp{}, ctx.Err()
+}