diff --git a/src/sound/backend/i_soundinternal.h b/src/sound/backend/i_soundinternal.h
index aac498b00..08dd311a2 100644
--- a/src/sound/backend/i_soundinternal.h
+++ b/src/sound/backend/i_soundinternal.h
@@ -22,6 +22,7 @@ enum EChanFlag
 
 	CHANF_PICKUP = CHANF_MAYBE_LOCAL,
 
+	CHANF_NONE = 0,
 	CHANF_IS3D = 1,		// internal: Sound is 3D.
 	CHANF_EVICTED = 2,		// internal: Sound was evicted.
 	CHANF_FORGETTABLE = 4,		// internal: Forget channel data when sound stops.
diff --git a/src/sound/s_doomsound.cpp b/src/sound/s_doomsound.cpp
index 165481c70..d2f551597 100644
--- a/src/sound/s_doomsound.cpp
+++ b/src/sound/s_doomsound.cpp
@@ -85,7 +85,7 @@ class DoomSoundEngine : public SoundEngine
 {
 	// client specific parts of the sound engine go in this class.
 
-	void CalcPosVel(int type, const void* source, const float pt[3], int channum, int chanflags, FSoundID soundid, FVector3* pos, FVector3* vel) override;
+	void CalcPosVel(int type, const void* source, const float pt[3], int channum, int chanflags, FSoundID soundid, FVector3* pos, FVector3* vel, FSoundChan *) override;
 	bool ValidatePosVel(int sourcetype, const void* source, const FVector3& pos, const FVector3& vel);
 	TArray<uint8_t> ReadSound(int lumpnum);
 	int PickReplacement(int refid);
@@ -892,7 +892,7 @@ static void CalcPolyobjSoundOrg(const DVector3& listenpos, const FPolyObj* poly,
 //
 //=========================================================================
 
-void DoomSoundEngine::CalcPosVel(int type, const void* source, const float pt[3], int channum, int chanflags, FSoundID soundid, FVector3* pos, FVector3* vel)
+void DoomSoundEngine::CalcPosVel(int type, const void* source, const float pt[3], int channum, int chanflags, FSoundID soundid, FVector3* pos, FVector3* vel, FSoundChan *)
 {
 	if (pos != nullptr)
 	{
diff --git a/src/sound/s_sound.cpp b/src/sound/s_sound.cpp
index 832ad145e..d07b744d2 100644
--- a/src/sound/s_sound.cpp
+++ b/src/sound/s_sound.cpp
@@ -335,7 +335,7 @@ FString SoundEngine::ListSoundChannels()
 
 void SoundEngine::CalcPosVel(FSoundChan *chan, FVector3 *pos, FVector3 *vel)
 {
-	CalcPosVel(chan->SourceType, chan->Source, chan->Point,	chan->EntChannel, chan->ChanFlags, chan->OrgID, pos, vel);
+	CalcPosVel(chan->SourceType, chan->Source, chan->Point,	chan->EntChannel, chan->ChanFlags, chan->OrgID, pos, vel, chan);
 }
 
 bool SoundEngine::ValidatePosVel(const FSoundChan* const chan, const FVector3& pos, const FVector3& vel)
@@ -397,7 +397,7 @@ FSoundChan *SoundEngine::StartSound(int type, const void *source,
 
 	org_id = sound_id;
 
-	CalcPosVel(type, source, &pt->X, channel, chanflags, sound_id, &pos, &vel);
+	CalcPosVel(type, source, &pt->X, channel, chanflags, sound_id, &pos, &vel, nullptr);
 
 	if (!ValidatePosVel(type, source, pos, vel))
 	{
@@ -577,7 +577,7 @@ FSoundChan *SoundEngine::StartSound(int type, const void *source,
 		if (chanflags & (CHANF_UI|CHANF_NOPAUSE)) startflags |= SNDF_NOPAUSE;
 		if (chanflags & CHANF_UI) startflags |= SNDF_NOREVERB;
 
-		if (attenuation > 0)
+		if (attenuation > 0 && type != SOURCE_None)
 		{
             LoadSound3D(sfx, &SoundBuffer);
             chan = (FSoundChan*)GSnd->StartSound3D (sfx->data3d, &listener, float(volume), rolloff, float(attenuation), pitch, basepriority, pos, vel, channel, startflags, NULL);
@@ -727,7 +727,8 @@ sfxinfo_t *SoundEngine::LoadSound(sfxinfo_t *sfx, FSoundLoadBuffer *pBuffer)
 		// then set this one up as a link, and don't load the sound again.
 		for (i = 0; i < S_sfx.Size(); i++)
 		{
-			if (S_sfx[i].data.isValid() && S_sfx[i].link == sfxinfo_t::NO_LINK && S_sfx[i].lumpnum == sfx->lumpnum)
+			if (S_sfx[i].data.isValid() && S_sfx[i].link == sfxinfo_t::NO_LINK && S_sfx[i].lumpnum == sfx->lumpnum &&
+				(!sfx->bLoadRAW || (sfx->RawRate == S_sfx[i].RawRate)))	// Raw sounds with different sample rates may not share buffers, even if they use the same source data.
 			{
 				//DPrintf (DMSG_NOTIFY, "Linked %s to %s (%d)\n", sfx->name.GetChars(), S_sfx[i].name.GetChars(), i);
 				sfx->link = i;
@@ -1060,6 +1061,16 @@ void SoundEngine::ChangeSoundVolume(int sourcetype, const void *source, int chan
 	return;
 }
 
+void SoundEngine::SetVolume(FSoundChan* chan, float volume)
+{
+	if (volume < 0.0) volume = 0.0;
+	else if (volume > 1.0) volume = 1.0;
+
+	assert(chan != nullptr);
+	GSnd->ChannelVolume(chan, volume);
+	chan->Volume = volume;
+}
+
 //==========================================================================
 //
 // S_ChangeSoundPitch
@@ -1153,7 +1164,7 @@ bool SoundEngine::IsSourcePlayingSomething (int sourcetype, const void *actor, i
 {
 	for (FSoundChan *chan = Channels; chan != NULL; chan = chan->NextChan)
 	{
-		if (chan->SourceType == sourcetype && chan->Source == actor)
+		if (chan->SourceType == sourcetype && (sourcetype == SOURCE_None || sourcetype == SOURCE_Unattached || chan->Source == actor))
 		{
 			if ((channel == 0 || chan->EntChannel == channel) && (sound_id <= 0 || chan->OrgID == sound_id))
 			{
@@ -1558,6 +1569,14 @@ int SoundEngine::AddSoundLump(const char* logicalname, int lump, int CurrentPitc
 	return (int)S_sfx.Size()-1;
 }
 
+int SoundEngine::AddSfx(sfxinfo_t &sfx)
+{
+	S_sfx.Push(sfx);
+	if (sfx.ResourceId >= 0) ResIdMap[sfx.ResourceId] = S_sfx.Size() - 1;
+	return (int)S_sfx.Size() - 1;
+}
+
+
 //==========================================================================
 //
 // S_FindSoundTentative
diff --git a/src/sound/s_soundinternal.h b/src/sound/s_soundinternal.h
index bbcd73370..2865e766b 100644
--- a/src/sound/s_soundinternal.h
+++ b/src/sound/s_soundinternal.h
@@ -262,7 +262,7 @@ private:
 
 	bool IsChannelUsed(int sourcetype, const void* actor, int channel, int* seen);
 	// This is the actual sound positioning logic which needs to be provided by the client.
-	virtual void CalcPosVel(int type, const void* source, const float pt[3], int channel, int chanflags, FSoundID chanSound, FVector3* pos, FVector3* vel) = 0;
+	virtual void CalcPosVel(int type, const void* source, const float pt[3], int channel, int chanflags, FSoundID chanSound, FVector3* pos, FVector3* vel, FSoundChan *chan) = 0;
 	// This can be overridden by the clent to provide some diagnostics. The default lets everything pass.
 	virtual bool ValidatePosVel(int sourcetype, const void* source, const FVector3& pos, const FVector3& vel) { return true; }
 
@@ -293,6 +293,7 @@ public:
 
 	void StopAllChannels(void);
 	void SetPitch(FSoundChan* chan, float dpitch);
+	void SetVolume(FSoundChan* chan, float vol);
 
 	FSoundChan* GetChannel(void* syschan);
 	void RestoreEvictedChannels();
@@ -316,7 +317,7 @@ public:
 	void RelinkSound(int sourcetype, const void* from, const void* to, const FVector3* optpos);
 	void ChangeSoundVolume(int sourcetype, const void* source, int channel, double dvolume);
 	void ChangeSoundPitch(int sourcetype, const void* source, int channel, double pitch, int sound_id = -1);
-	bool IsSourcePlayingSomething(int sourcetype, const void* actor, int channel, int sound_id);
+	bool IsSourcePlayingSomething(int sourcetype, const void* actor, int channel, int sound_id = -1);
 
 	// Stop and resume music, during game PAUSE.
 	int GetSoundPlayingInfo(int sourcetype, const void* source, int sound_id);
@@ -375,12 +376,17 @@ public:
 	{
 		S_rnd.Clear();
 	}
+	bool isValidSoundId(int id)
+	{
+		return id > 0 && id < (int)S_sfx.Size() && !S_sfx[id].bTentative && S_sfx[id].lumpnum != sfx_empty;
+	}
 
 	template<class func> bool EnumerateChannels(func callback)
 	{
 		for (FSoundChan* chan = Channels; chan; chan = chan->NextChan)
 		{
-			if (callback(chan)) return true;
+			int res = callback(chan);
+			if (res) return res > 0;
 		}
 		return false;
 	}
@@ -403,6 +409,7 @@ public:
 	int FindSoundNoHash(const char* logicalname);
 	int FindSoundByLump(int lump);
 	int AddSoundLump(const char* logicalname, int lump, int CurrentPitchMask, int resid = -1, int nearlimit = 2);
+	int AddSfx(sfxinfo_t &sfx);
 	int FindSoundTentative(const char* name);
 	void CacheRandomSound(sfxinfo_t* sfx);
 	unsigned int GetMSLength(FSoundID sound);