diff --git a/libraries/zmusic/zmusic/zmusic.h b/libraries/zmusic/zmusic/zmusic.h
index 309a3f26b..4847ae81f 100644
--- a/libraries/zmusic/zmusic/zmusic.h
+++ b/libraries/zmusic/zmusic/zmusic.h
@@ -149,10 +149,11 @@ void SetWgOpn(const void* data, unsigned len);
 // Set DMXGUS data for running the GUS synth in actual GUS mode.
 void SetDmxGus(const void* data, unsigned len);
 
-// These exports is needed by the MIDI dumpers which need to remain on the client side.
+// These exports are needed by the MIDI dumpers which need to remain on the client side.
 class MIDISource;	// abstract for the client
 EMIDIType IdentifyMIDIType(uint32_t *id, int size);
 MIDISource *CreateMIDISource(const uint8_t *data, size_t length, EMIDIType miditype);
+void MIDIDumpWave(MIDISource* source, EMidiDevice devtype, const char* devarg, const char* outname, int subsong, int samplerate);
 
 class MusInfo;
 // Configuration interface. The return value specifies if a music restart is needed.
diff --git a/src/menu/menudef.cpp b/src/menu/menudef.cpp
index 15e994a9d..506cbf30e 100644
--- a/src/menu/menudef.cpp
+++ b/src/menu/menudef.cpp
@@ -51,6 +51,7 @@
 #include "teaminfo.h"
 #include "r_data/sprites.h"
 #include "atterm.h"
+#include "zmusic/zmusic.h"
 
 
 void ClearSaveGames();
diff --git a/src/playsim/p_acs.cpp b/src/playsim/p_acs.cpp
index b9f30cdd4..9a547aaa1 100644
--- a/src/playsim/p_acs.cpp
+++ b/src/playsim/p_acs.cpp
@@ -69,7 +69,6 @@
 #include "p_effect.h"
 #include "r_utility.h"
 #include "a_morph.h"
-#include "i_music.h"
 #include "thingdef.h"
 #include "g_levellocals.h"
 #include "actorinlines.h"
diff --git a/src/scripting/vmthunks.cpp b/src/scripting/vmthunks.cpp
index b8ccdbbcd..d21fe0394 100644
--- a/src/scripting/vmthunks.cpp
+++ b/src/scripting/vmthunks.cpp
@@ -46,7 +46,6 @@
 #include "a_weapons.h"
 #include "d_player.h"
 #include "p_setup.h"
-#include "i_music.h"
 #include "am_map.h"
 #include "v_video.h"
 #include "gi.h"
diff --git a/src/sound/backend/oalsound.cpp b/src/sound/backend/oalsound.cpp
index 3236b2b32..39674b9a9 100644
--- a/src/sound/backend/oalsound.cpp
+++ b/src/sound/backend/oalsound.cpp
@@ -41,7 +41,6 @@
 #include "c_dispatch.h"
 #include "v_text.h"
 #include "i_module.h"
-#include "i_music.h"
 #include "cmdlib.h"
 #include "menu/menu.h"
 #include "zmusic/sounddecoder.h"
diff --git a/src/sound/music/i_music.cpp b/src/sound/music/i_music.cpp
index 0ef50443d..dd7f02d32 100644
--- a/src/sound/music/i_music.cpp
+++ b/src/sound/music/i_music.cpp
@@ -45,17 +45,19 @@
 #include "c_dispatch.h"
 #include "templates.h"
 #include "stats.h"
+#include "c_cvars.h"
 #include "c_console.h"
 #include "vm.h"
 #include "v_text.h"
+#include "i_sound.h"
 #include "i_soundfont.h"
 #include "s_music.h"
+#include "doomstat.h"
 #include "zmusic/zmusic.h"
 #include "zmusic/musinfo.h"
 #include "streamsources/streamsource.h"
 #include "filereadermusicinterface.h"
 #include "../libraries/zmusic/midisources/midisource.h"
-#include "../libraries/dumb/include/dumb.h"
 
 #define GZIP_ID1		31
 #define GZIP_ID2		139
@@ -68,9 +70,9 @@
 #define GZIP_FNAME		8
 #define GZIP_FCOMMENT	16
 
-extern int MUSHeaderSearch(const uint8_t *head, int len);
+
 void I_InitSoundFonts();
-extern "C" void dumb_exit();
+
 extern MusPlayingInfo mus_playing;
 
 EXTERN_CVAR (Int, snd_samplerate)
@@ -80,7 +82,6 @@ static bool MusicDown = true;
 
 static bool ungzip(uint8_t *data, int size, std::vector<uint8_t> &newdata);
 
-MusInfo *currSong;
 int		nomusic = 0;
 
 //==========================================================================
@@ -275,16 +276,14 @@ void I_ShutdownMusic(bool onexit)
 	if (MusicDown)
 		return;
 	MusicDown = true;
-	if (currSong)
+	if (mus_playing.handle)
 	{
 		S_StopMusic (true);
-		assert (currSong == nullptr);
+		assert (mus_playing.handle == nullptr);
 	}
 	if (onexit)
 	{
-		// free static data in the backends.
-		TimidityPP_Shutdown();
-		dumb_exit();
+		ZMusic_Shutdown();
 	}
 }
 
@@ -294,7 +293,7 @@ void I_ShutdownMusic(bool onexit)
 //
 //==========================================================================
 
-MusInfo *I_RegisterSong (MusicIO::FileInterface *reader, MidiDeviceSetting *device)
+MusInfo *I_RegisterSong (MusicIO::FileInterface *reader, EMidiDevice device, const char *Args)
 {
 	MusInfo *info = nullptr;
 	StreamSource *streamsource = nullptr;
@@ -357,14 +356,13 @@ MusInfo *I_RegisterSong (MusicIO::FileInterface *reader, MidiDeviceSetting *devi
 				return nullptr;
 			}
 
-			EMidiDevice devtype = device == nullptr ? MDEV_DEFAULT : (EMidiDevice)device->device;
 #ifndef _WIN32
 			// non-Windows platforms don't support MDEV_MMAPI so map to MDEV_SNDSYS
-			if (devtype == MDEV_MMAPI)
-				devtype = MDEV_SNDSYS;
+			if (device == MDEV_MMAPI)
+				device = MDEV_SNDSYS;
 #endif
 
-			info = CreateMIDIStreamer(source, devtype, device != nullptr ? device->args.GetChars() : "");
+			info = CreateMIDIStreamer(source, device, Args? Args : "");
 		}
 
 		// Check for CDDA "format"
@@ -546,15 +544,6 @@ static bool ungzip(uint8_t *data, int complen, std::vector<uint8_t> &newdata)
 //
 //==========================================================================
 
-void I_UpdateMusic()
-{
-	if (currSong != nullptr)
-	{
-		currSong->Update();
-	}
-}
-
-
 void I_SetRelativeVolume(float vol)
 {
 	relative_volume = (float)vol;
diff --git a/src/sound/music/i_music.h b/src/sound/music/i_music.h
index c2639b2f0..54502461b 100644
--- a/src/sound/music/i_music.h
+++ b/src/sound/music/i_music.h
@@ -34,10 +34,6 @@
 #ifndef __I_MUSIC_H__
 #define __I_MUSIC_H__
 
-#include "doomdef.h"
-#include "zmusic/mididefs.h"
-#include "i_soundinternal.h"
-
 class FileReader;
 struct FOptionValues;
 
@@ -47,17 +43,11 @@ struct FOptionValues;
 void I_InitMusic ();
 void I_ShutdownMusic (bool onexit = false);
 void I_BuildMIDIMenuList (FOptionValues *);
-void I_UpdateMusic ();
 
 // Volume.
 void I_SetRelativeVolume(float);
 void I_SetMusicVolume (double volume);
 
-// Registers a song handle to song data.
-class MusInfo;
-struct MidiDeviceSetting;
-MusInfo *I_RegisterSong (MusicIO::FileInterface *reader, MidiDeviceSetting *device);
-MusInfo *I_RegisterCDSong (int track, int cdid = 0);
 
 extern int nomusic;
 
diff --git a/src/sound/music/i_musicinterns.h b/src/sound/music/i_musicinterns.h
index 95686ef70..c316ba27d 100644
--- a/src/sound/music/i_musicinterns.h
+++ b/src/sound/music/i_musicinterns.h
@@ -1,42 +1,32 @@
 
+#include <stdint.h>
 #include <mutex>
 #include <string>
-#include "c_cvars.h"
-#include "i_sound.h"
-#include "i_music.h"
-#include "s_sound.h"
-#include "files.h"
-#include "zmusic/midiconfig.h"
-#include "zmusic/mididefs.h"
-
-#include "zmusic/..//mididevices/mididevice.h"	// this is still needed...
-
-void I_InitMusicWin32 ();
+#include "zmusic/zmusic.h"
 
 class MIDISource;
 class MIDIDevice;
 class OPLmusicFile;
-
-
-// Data interface
-
-// Module played via foo_dumb -----------------------------------------------
-
 class StreamSource;
-
-// stream song ------------------------------------------
+class MusInfo;
 
 MusInfo *OpenStreamSong(StreamSource *source);
 const char *GME_CheckFormat(uint32_t header);
 MusInfo* CDDA_OpenSong(MusicIO::FileInterface* reader);
 MusInfo* CD_OpenSong(int track, int id);
 MusInfo* CreateMIDIStreamer(MIDISource *source, EMidiDevice devtype, const char* args);
-void MIDIDumpWave(MIDISource* source, EMidiDevice devtype, const char* devarg, const char* outname, int subsong, int samplerate);
 
-// --------------------------------------------------------------------------
+// Registers a song handle to song data.
 
-extern MusInfo *currSong;
-void MIDIDeviceChanged(int newdev, bool force = false);
+MusInfo *I_RegisterSong (MusicIO::FileInterface *reader, EMidiDevice device, const char *Args);
+MusInfo *I_RegisterCDSong (int track, int cdid = 0);
 
-EXTERN_CVAR (Float, snd_mastervolume)
-EXTERN_CVAR (Float, snd_musicvolume)
+void TimidityPP_Shutdown();
+extern "C" void dumb_exit();
+
+inline void ZMusic_Shutdown()
+{
+	// free static data in the backends.
+	TimidityPP_Shutdown();
+	dumb_exit();
+}
diff --git a/src/sound/music/music_config.cpp b/src/sound/music/music_config.cpp
index ac538c412..2531be803 100644
--- a/src/sound/music/music_config.cpp
+++ b/src/sound/music/music_config.cpp
@@ -33,7 +33,9 @@
 **
 */
 
-#include "i_musicinterns.h"
+#include <stdint.h>
+#include <mutex>
+#include <string>
 #include "c_cvars.h"
 #include "s_music.h"
 #include "zmusic/zmusic.h"
diff --git a/src/sound/music/music_midi_base.cpp b/src/sound/music/music_midi_base.cpp
index e335461ff..6d08fe0e7 100644
--- a/src/sound/music/music_midi_base.cpp
+++ b/src/sound/music/music_midi_base.cpp
@@ -38,7 +38,6 @@
 #include <mmsystem.h>
 #endif
 
-#include "i_musicinterns.h"
 #include "c_dispatch.h"
 
 #include "v_text.h"
diff --git a/src/sound/s_music.cpp b/src/sound/s_music.cpp
index cf052f8bc..d0fc7a800 100644
--- a/src/sound/s_music.cpp
+++ b/src/sound/s_music.cpp
@@ -89,6 +89,8 @@
 #include "filereadermusicinterface.h"
 #include "zmusic/musinfo.h"
 
+#include "i_musicinterns.h"
+
 // MACROS ------------------------------------------------------------------
 
 
@@ -269,17 +271,18 @@ void S_ResumeMusic ()
 
 void S_UpdateMusic ()
 {
-	I_UpdateMusic();
-	
-	// [RH] Update music and/or playlist. IsPlaying() must be called
-	// to attempt to reconnect to broken net streams and to advance the
-	// playlist when the current song finishes.
-	if (mus_playing.handle != nullptr &&
-		!mus_playing.handle->IsPlaying() &&
-		PlayList)
+	if (mus_playing.handle != nullptr)
 	{
-		PlayList->Advance();
-		S_ActivatePlayList(false);
+		mus_playing.handle->Update();
+		
+		// [RH] Update music and/or playlist. IsPlaying() must be called
+		// to attempt to reconnect to broken net streams and to advance the
+		// playlist when the current song finishes.
+		if (!mus_playing.handle->IsPlaying() && PlayList)
+		{
+			PlayList->Advance();
+			S_ActivatePlayList(false);
+		}
 	}
 }
 
@@ -540,7 +543,7 @@ bool S_ChangeMusic (const char *musicname, int order, bool looping, bool force)
 			try
 			{
 				auto mreader = new FileReaderMusicInterface(reader);
-				mus_playing.handle = I_RegisterSong(mreader, devp);
+				mus_playing.handle = I_RegisterSong(mreader, devp? (EMidiDevice)devp->device : MDEV_DEFAULT, devp? devp->args.GetChars() : "");
 			}
 			catch (const std::runtime_error& err)
 			{