@@ -37,11 +37,11 @@ envelope(Apu *c, Uint32 age)

 	return 0x0000;

 }

-void

+int

 apu_render(Apu *c, Sint16 *sample, Sint16 *end)

 {

 	Sint32 s;

-	if(!c->advance || !c->period) return;

+	if(!c->advance || !c->period) return 0;

 	while(sample < end) {

 		c->count += c->advance;

 		c->i += c->count / c->period;

@@ -49,7 +49,7 @@ apu_render(Apu *c, Sint16 *sample, Sint16 *end)

 		if(c->i >= c->len) {

 			if(!c->repeat) {

 				c->advance = 0;

-				return;

+				return 1;

 			}

 			c->i %= c->len;

 		}

@@ -57,6 +57,7 @@ apu_render(Apu *c, Sint16 *sample, Sint16 *end)

 		*sample++ += s * c->volume[0] / 0x180;

 		*sample++ += s * c->volume[1] / 0x180;

 	}

+	return 1;

 }

 void

@@ -24,6 +24,6 @@ typedef struct {

 	Uint8 pitch, repeat;

 } Apu;

-void apu_render(Apu *c, Sint16 *sample, Sint16 *end);

+int apu_render(Apu *c, Sint16 *sample, Sint16 *end);

 void apu_start(Apu *c, Uint16 adsr, Uint8 pitch);

 Uint8 apu_get_vu(Apu *c);

@@ -51,11 +51,13 @@ error(char *msg, const char *err)

 static void

 audio_callback(void *u, Uint8 *stream, int len)

 {

-	int i;

+	int i, running = 0;

 	Sint16 *samples = (Sint16 *)stream;

 	SDL_memset(stream, 0, len);

 	for(i = 0; i < POLYPHONY; ++i)

-		apu_render(&apu[i], samples, samples + len / 2);

+		running += apu_render(&apu[i], samples, samples + len / 2);

+	if(!running)

+		SDL_PauseAudioDevice(audio_id, 1);

 	(void)u;

 }

@@ -162,7 +164,6 @@ init(void)

 	audio_id = SDL_OpenAudioDevice(NULL, 0, &as, NULL, 0);

 	if(!audio_id)

 		return error("Audio", SDL_GetError());

-	SDL_PauseAudioDevice(audio_id, 0);

 	return 1;

 }

@@ -300,6 +301,7 @@ audio_talk(Device *d, Uint8 b0, Uint8 w)

 		c->repeat = !(d->dat[0xf] & 0x80);

 		apu_start(c, mempeek16(d->dat, 0x8), d->dat[0xf] & 0x7f);

 		SDL_UnlockAudioDevice(audio_id);

+		SDL_PauseAudioDevice(audio_id, 0);

 	}

 }