4 files changed, 51 insertions, 3 deletions

diff --git a/engines/gob/detection.cpp b/engines/gob/detection.cpp
index 2711d368fd..605cb90e55 100644
--- a/engines/gob/detection.cpp
+++ b/engines/gob/detection.cpp
@@ -316,6 +316,18 @@ static const GOBGameDescription gameDescriptions[] = {
 		GF_GOB2,
 		"intro"
 	},
+	{ // Supplied by arcepi in bug report #1659884
+		{
+			"gob2",
+			"",
+			AD_ENTRY1s("intro.stk", "5f53c56e3aa2f1e76c2e4f0caa15887f", 829232),
+			ES_ESP,
+			kPlatformPC,
+			Common::ADGF_NO_FLAGS
+		},
+		GF_GOB2,
+		"intro"
+	},
 	{
 		{
 			"gob2",
diff --git a/engines/gob/inter_v1.cpp b/engines/gob/inter_v1.cpp
index e11f452287..7e066cc1b7 100644
--- a/engines/gob/inter_v1.cpp
+++ b/engines/gob/inter_v1.cpp
@@ -1467,8 +1467,9 @@ bool Inter_v1::o1_keyFunc(char &cmdCount, int16 &counter, int16 &retFlag) {
 
 		if (flag != 1) {
 			if (flag != 2) {
+				_vm->_snd->speakerOnUpdate(flag);
 				if (flag < 20) {
-					_vm->_util->delay(flag * 2);
+					_vm->_util->delay(flag);
 					_noBusyWait = true;
 				}
 				else
diff --git a/engines/gob/sound.cpp b/engines/gob/sound.cpp
index c39eb1165d..fd8d7488cb 100644
--- a/engines/gob/sound.cpp
+++ b/engines/gob/sound.cpp
@@ -36,6 +36,7 @@ Snd::SquareWaveStream::SquareWaveStream() {
 	_periodSamples = 0;
 	_remainingSamples = 0;
 	_sampleValue = 0;
+	_mixedSamples = 0;
 }
 
 void Snd::SquareWaveStream::playNote(int freq, int32 ms, uint rate) {
@@ -50,6 +51,29 @@ void Snd::SquareWaveStream::playNote(int freq, int32 ms, uint rate) {
 		_remainingSamples = (_rate * ms) / 1000;
 		_beepForever = false;
 	}
+	_mixedSamples = 0;
+}
+
+void Snd::SquareWaveStream::stop(uint32 milis) {
+	if (!_beepForever)
+		return;
+
+	if (milis)
+		update(milis);
+	else
+		_remainingSamples = 0;
+}
+
+void Snd::SquareWaveStream::update(uint32 milis) {
+	uint32 neededSamples;
+
+	if (!_beepForever || !_remainingSamples)
+		return;
+
+	neededSamples = (_rate * milis) / 1000;
+	_remainingSamples =
+		neededSamples > _mixedSamples ? neededSamples - _mixedSamples : 0;
+	_beepForever = false;
 }
 
 int Snd::SquareWaveStream::readBuffer(int16 *buffer, const int numSamples) {
@@ -65,6 +89,7 @@ int Snd::SquareWaveStream::readBuffer(int16 *buffer, const int numSamples) {
 		}
 		if (!_beepForever)
 			_remainingSamples--;
+		_mixedSamples++;
 	}
 
 	return numSamples;
@@ -107,10 +132,15 @@ void Snd::setBlasterPort(int16 port) {return;}
 
 void Snd::speakerOn(int16 frequency, int32 length) {
 	_speakerStream.playNote(frequency, length, _vm->_mixer->getOutputRate());
+	_speakerStartTimeKey = _vm->_util->getTimeKey();
 }
 
 void Snd::speakerOff(void) {
-	_speakerStream.stop();
+	_speakerStream.stop(_vm->_util->getTimeKey() - _speakerStartTimeKey);
+}
+
+void Snd::speakerOnUpdate(uint32 milis) {
+	_speakerStream.update(milis);
 }
 
 void Snd::stopSound(int16 fadeLength)
diff --git a/engines/gob/sound.h b/engines/gob/sound.h
index 4a614fc8cc..8d7ffd7b8d 100644
--- a/engines/gob/sound.h
+++ b/engines/gob/sound.h
@@ -51,6 +51,7 @@ public:
 	Snd(GobEngine *vm);
 	void speakerOn(int16 frequency, int32 length);
 	void speakerOff(void);
+	void speakerOnUpdate(uint32 milis);
 	SoundDesc *loadSoundData(const char *path);
 	void stopSound(int16 fadeLength);
 	void playSample(SoundDesc *sndDesc, int16 repCount, int16 frequency, int16 fadeLength = 0);
@@ -79,6 +80,7 @@ protected:
 		uint32 _periodLength;
 		uint32 _periodSamples;
 		uint32 _remainingSamples;
+		uint32 _mixedSamples;
 		int16 _sampleValue;
 
 	public:
@@ -86,7 +88,8 @@ protected:
 		~SquareWaveStream() {}
 
 		void playNote(int freq, int32 ms, uint rate);
-		void stop(void) { _remainingSamples = 0; }
+		void update(uint32 milis);
+		void stop(uint32 milis);
 
 		int readBuffer(int16 *buffer, const int numSamples);
 
@@ -98,6 +101,8 @@ protected:
 
 	SquareWaveStream _speakerStream;
 	Audio::SoundHandle _speakerHandle;
+	uint32 _speakerStartTimeKey;
+
 	Audio::SoundHandle *_activeHandle;
 	Audio::SoundHandle _compositionHandle;