diff --git a/src/oplsynth/music_opl_mididevice.cpp b/src/oplsynth/music_opl_mididevice.cpp
index f6cfab30e..1a7894028 100644
--- a/src/oplsynth/music_opl_mididevice.cpp
+++ b/src/oplsynth/music_opl_mididevice.cpp
@@ -95,7 +95,7 @@ OPLMIDIDevice::OPLMIDIDevice(const char *args)
 //
 //==========================================================================
 
-int OPLMIDIDevice::Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata)
+int OPLMIDIDevice::Open(MidiCallback callback, void *userdata)
 {
 	if (io == NULL || 0 == (NumChips = io->OPLinit(opl_numchips, FullPan, true)))
 	{
diff --git a/src/sound/i_musicinterns.h b/src/sound/i_musicinterns.h
index 060e72e49..d8638afcf 100644
--- a/src/sound/i_musicinterns.h
+++ b/src/sound/i_musicinterns.h
@@ -79,13 +79,14 @@ typedef uint8_t *LPSTR;
 
 class MIDIStreamer;
 
+typedef void(*MidiCallback)(unsigned int, void *);
 class MIDIDevice
 {
 public:
 	MIDIDevice();
 	virtual ~MIDIDevice();
 
-	virtual int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata) = 0;
+	virtual int Open(MidiCallback, void *userdata) = 0;
 	virtual void Close() = 0;
 	virtual bool IsOpen() const = 0;
 	virtual int GetTechnology() const = 0;
@@ -118,7 +119,7 @@ class WinMIDIDevice : public MIDIDevice
 public:
 	WinMIDIDevice(int dev_id);
 	~WinMIDIDevice();
-	int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int Open(MidiCallback, void *userdata);
 	void Close();
 	bool IsOpen() const;
 	int GetTechnology() const;
@@ -143,7 +144,7 @@ protected:
 	DWORD SavedVolume;
 	bool VolumeWorks;
 
-	void (*Callback)(unsigned int, void *, DWORD, DWORD);
+	void (*Callback)(unsigned int, void *);
 	void *CallbackData;
 };
 #endif
@@ -155,7 +156,7 @@ protected:
 class AudioToolboxMIDIDevice : public MIDIDevice
 {
 public:
-	virtual int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userData) override;
+	virtual int Open(MidiCallback, void *userData) override;
 	virtual void Close() override;
 	virtual bool IsOpen() const override;
 	virtual int GetTechnology() const override;
@@ -217,7 +218,7 @@ protected:
 class SndSysMIDIDevice : public PseudoMIDIDevice
 {
 public:
-	int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int Open(MidiCallback, void *userdata);
 	bool Preprocess(MIDIStreamer *song, bool looping);
 };
 
@@ -229,7 +230,7 @@ public:
 	TimidityPPMIDIDevice(const char *args);
 	~TimidityPPMIDIDevice();
 
-	int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int Open(MidiCallback, void *userdata);
 	bool Preprocess(MIDIStreamer *song, bool looping);
 	bool IsOpen() const;
 	int Resume();
@@ -292,12 +293,12 @@ protected:
 	DWORD Position;
 	int SampleRate;
 
-	void (*Callback)(unsigned int, void *, DWORD, DWORD);
+	void (*Callback)(unsigned int, void *);
 	void *CallbackData;
 
 	virtual void CalcTickRate();
 	int PlayTick();
-	int OpenStream(int chunks, int flags, void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int OpenStream(int chunks, int flags, MidiCallback, void *userdata);
 	static bool FillStream(SoundStream *stream, void *buff, int len, void *userdata);
 	virtual bool ServiceStream (void *buff, int numbytes);
 
@@ -312,7 +313,7 @@ class OPLMIDIDevice : public SoftSynthMIDIDevice, protected OPLmusicBlock
 {
 public:
 	OPLMIDIDevice(const char *args);
-	int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int Open(MidiCallback, void *userdata);
 	void Close();
 	int GetTechnology() const;
 	FString GetStats();
@@ -347,7 +348,7 @@ public:
 	TimidityMIDIDevice(const char *args);
 	~TimidityMIDIDevice();
 
-	int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int Open(MidiCallback, void *userdata);
 	void PrecacheInstruments(const uint16_t *instruments, int count);
 	FString GetStats();
 
@@ -381,7 +382,7 @@ public:
 	WildMIDIDevice(const char *args);
 	~WildMIDIDevice();
 
-	int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int Open(MidiCallback, void *userdata);
 	void PrecacheInstruments(const uint16_t *instruments, int count);
 	FString GetStats();
 
@@ -413,7 +414,7 @@ public:
 	FluidSynthMIDIDevice(const char *args);
 	~FluidSynthMIDIDevice();
 
-	int Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata);
+	int Open(MidiCallback, void *userdata);
 	FString GetStats();
 	void FluidSettingInt(const char *setting, int value);
 	void FluidSettingNum(const char *setting, double value);
@@ -505,7 +506,7 @@ protected:
 	static EMidiDevice SelectMIDIDevice(EMidiDevice devtype);
 	MIDIDevice *CreateMIDIDevice(EMidiDevice devtype) const;
 
-	static void Callback(unsigned int uMsg, void *userdata, DWORD dwParam1, DWORD dwParam2);
+	static void Callback(unsigned int uMsg, void *userdata);
 
 	// Virtuals for subclasses to override
 	virtual void StartPlayback();
diff --git a/src/sound/music_audiotoolbox_mididevice.cpp b/src/sound/music_audiotoolbox_mididevice.cpp
index 8ff54e141..8d36a0f5a 100644
--- a/src/sound/music_audiotoolbox_mididevice.cpp
+++ b/src/sound/music_audiotoolbox_mididevice.cpp
@@ -40,7 +40,7 @@
 	}                                                              \
 }
 
-int AudioToolboxMIDIDevice::Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userData)
+int AudioToolboxMIDIDevice::Open(MidiCallback callback, void *userData)
 {
 	AT_MIDI_CHECK_ERROR(NewMusicPlayer(&m_player), false);
 	AT_MIDI_CHECK_ERROR(NewMusicSequence(&m_sequence), false);
diff --git a/src/sound/music_fluidsynth_mididevice.cpp b/src/sound/music_fluidsynth_mididevice.cpp
index 793fce0b1..087a0ce3d 100644
--- a/src/sound/music_fluidsynth_mididevice.cpp
+++ b/src/sound/music_fluidsynth_mididevice.cpp
@@ -372,7 +372,7 @@ FluidSynthMIDIDevice::~FluidSynthMIDIDevice()
 //
 //==========================================================================
 
-int FluidSynthMIDIDevice::Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata)
+int FluidSynthMIDIDevice::Open(MidiCallback callback, void *userdata)
 {
 	if (FluidSynth == NULL)
 	{
diff --git a/src/sound/music_midi_timidity.cpp b/src/sound/music_midi_timidity.cpp
index 2f4025ca6..c3fbe31b1 100644
--- a/src/sound/music_midi_timidity.cpp
+++ b/src/sound/music_midi_timidity.cpp
@@ -178,7 +178,7 @@ bool TimidityPPMIDIDevice::Preprocess(MIDIStreamer *song, bool looping)
 //
 //==========================================================================
 
-int TimidityPPMIDIDevice::Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata)
+int TimidityPPMIDIDevice::Open(MidiCallback callback, void *userdata)
 {
 	int pipeSize;
 
diff --git a/src/sound/music_midistream.cpp b/src/sound/music_midistream.cpp
index 83bdf6db7..58214d1a7 100644
--- a/src/sound/music_midistream.cpp
+++ b/src/sound/music_midistream.cpp
@@ -691,7 +691,7 @@ int MIDIStreamer::VolumeControllerChange(int channel, int volume)
 //
 //==========================================================================
 
-void MIDIStreamer::Callback(unsigned int uMsg, void *userdata, DWORD dwParam1, DWORD dwParam2)
+void MIDIStreamer::Callback(unsigned int uMsg, void *userdata)
 {
 	MIDIStreamer *self = (MIDIStreamer *)userdata;
 
diff --git a/src/sound/music_pseudo_mididevice.cpp b/src/sound/music_pseudo_mididevice.cpp
index ecfed0da2..388c31931 100644
--- a/src/sound/music_pseudo_mididevice.cpp
+++ b/src/sound/music_pseudo_mididevice.cpp
@@ -239,7 +239,7 @@ FString PseudoMIDIDevice::GetStats()
 //
 //==========================================================================
 
-int SndSysMIDIDevice::Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata)
+int SndSysMIDIDevice::Open(MidiCallback callback, void *userdata)
 {
 	return 0;
 }
diff --git a/src/sound/music_softsynth_mididevice.cpp b/src/sound/music_softsynth_mididevice.cpp
index 1d4086e02..d0e8b7ef5 100644
--- a/src/sound/music_softsynth_mididevice.cpp
+++ b/src/sound/music_softsynth_mididevice.cpp
@@ -95,7 +95,7 @@ SoftSynthMIDIDevice::~SoftSynthMIDIDevice()
 //
 //==========================================================================
 
-int SoftSynthMIDIDevice::OpenStream(int chunks, int flags, void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata)
+int SoftSynthMIDIDevice::OpenStream(int chunks, int flags, MidiCallback callback, void *userdata)
 {
 	int chunksize = (SampleRate / chunks) * 4;
 	if (!(flags & SoundStream::Mono))
@@ -363,7 +363,7 @@ int SoftSynthMIDIDevice::PlayTick()
 
 			if (Callback != NULL)
 			{
-				Callback(MOM_DONE, CallbackData, 0, 0);
+				Callback(MOM_DONE, CallbackData);
 			}
 		}
 
diff --git a/src/sound/music_timidity_mididevice.cpp b/src/sound/music_timidity_mididevice.cpp
index 443d2f6bd..afc570ae1 100644
--- a/src/sound/music_timidity_mididevice.cpp
+++ b/src/sound/music_timidity_mididevice.cpp
@@ -115,7 +115,7 @@ TimidityMIDIDevice::~TimidityMIDIDevice()
 //
 //==========================================================================
 
-int TimidityMIDIDevice::Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata)
+int TimidityMIDIDevice::Open(MidiCallback callback, void *userdata)
 {
 	int ret = OpenStream(2, 0, callback, userdata);
 	if (ret == 0)
diff --git a/src/sound/music_wildmidi_mididevice.cpp b/src/sound/music_wildmidi_mididevice.cpp
index db14a873b..c446105a8 100644
--- a/src/sound/music_wildmidi_mididevice.cpp
+++ b/src/sound/music_wildmidi_mididevice.cpp
@@ -142,7 +142,7 @@ WildMIDIDevice::~WildMIDIDevice()
 //
 //==========================================================================
 
-int WildMIDIDevice::Open(void (*callback)(unsigned int, void *, DWORD, DWORD), void *userdata)
+int WildMIDIDevice::Open(MidiCallback callback, void *userdata)
 {
 	if (Renderer == NULL)
 	{
diff --git a/src/sound/music_win_mididevice.cpp b/src/sound/music_win_mididevice.cpp
index 0da1297d2..f6b9bc21c 100644
--- a/src/sound/music_win_mididevice.cpp
+++ b/src/sound/music_win_mididevice.cpp
@@ -94,7 +94,7 @@ WinMIDIDevice::~WinMIDIDevice()
 //
 //==========================================================================
 
-int WinMIDIDevice::Open(void (*callback)(UINT, void *, DWORD, DWORD), void *userdata)
+int WinMIDIDevice::Open(MidiCallback callback, void *userdata)
 {
 	MMRESULT err;
 
@@ -400,7 +400,7 @@ void CALLBACK WinMIDIDevice::CallbackFunc(HMIDIOUT hOut, UINT uMsg, DWORD_PTR dw
 	WinMIDIDevice *self = (WinMIDIDevice *)dwInstance;
 	if (self->Callback != NULL)
 	{
-		self->Callback(uMsg, self->CallbackData, dwParam1, dwParam2);
+		self->Callback(uMsg, self->CallbackData);
 	}
 }