diff --git a/headers/os/midi/MidiSynth.h b/headers/os/midi/MidiSynth.h
index 9d6dd1661a..cf24322538 100644
--- a/headers/os/midi/MidiSynth.h
+++ b/headers/os/midi/MidiSynth.h
@@ -66,7 +66,7 @@ protected:
 	void* fSongVariables;
 	void* fPerformanceVariables;
 	bool fMidiQueue;
-
+	
 private:
 
 	friend class BSynth;
@@ -78,7 +78,11 @@ private:
 
 	virtual void Run();
 
-	uint32 _reserved[4];
+	bigtime_t creationTime;
+	int16 transpose;
+	bool inputEnabled;
+
+	uint32 _reserved;
 };
 
 #endif // _MIDI_SYNTH_H
diff --git a/headers/os/midi/Synth.h b/headers/os/midi/Synth.h
index 3b95222a70..70775ac714 100644
--- a/headers/os/midi/Synth.h
+++ b/headers/os/midi/Synth.h
@@ -32,6 +32,8 @@ typedef void (*synth_controller_hook) (
 class BMidiSynth;
 class BMidiSynthFile;
 
+namespace BPrivate { class BSoftSynth; }
+
 class BSynth 
 {
 public:
@@ -93,7 +95,13 @@ private:
 	virtual void _ReservedSynth3();
 	virtual void _ReservedSynth4();
 
-	uint32 _reserved[13];
+	void Init();
+	
+	BPrivate::BSoftSynth* synth;
+	synth_mode synthMode;
+	int32 clientCount;
+
+	uint32 _reserved[10];
 };
 
 extern _IMPEXP_MIDI BSynth* be_synth;