diff --git a/include/musyx/synth.h b/include/musyx/synth.h
index f7cc1ef7..25a1c84d 100644
--- a/include/musyx/synth.h
+++ b/include/musyx/synth.h
@@ -52,7 +52,7 @@ u8 synthFXGetMaxVoices(u16 fid);
 void synthPauseVolume(u8 volume, u16 time, u8 vGroup);
 bool dataRemoveFX(u16 gid);
 void voiceUnblock(u32 voice);
-void voiceRemovePriority(const SYNTH_VOICE* svoice);
+void voiceRemovePriority(SYNTH_VOICE* svoice);
 #ifdef __cplusplus
 }
 #endif
diff --git a/src/musyx/runtime/stream.c b/src/musyx/runtime/stream.c
index 41b89ec8..d6242eeb 100644
--- a/src/musyx/runtime/stream.c
+++ b/src/musyx/runtime/stream.c
@@ -622,7 +622,8 @@ void sndStreamFree(u32 stid) {
 
 u32 sndStreamActivate(u32 stid) {
   u32 i;        // r31
-  bool ret = 0; // r28
+  u32 ret; // r28
+  ret = 0;
   MUSY_ASSERT_MSG(sndActive, "Sound system is not initialized.");
   hwDisableIrq();
   i = GetPrivateIndex(stid);
diff --git a/src/musyx/runtime/synthmacros.c b/src/musyx/runtime/synthmacros.c
index df5e7a09..48dd09f8 100644
--- a/src/musyx/runtime/synthmacros.c
+++ b/src/musyx/runtime/synthmacros.c
@@ -751,7 +751,11 @@ static u32 TranslateVolume(u32 volume, u16 curve) {
 
       if (vhigh < 0x7f) {
         d = vlow * (ptr[vhigh + 1] - ptr[vhigh]);
+#if MUSY_VERSION >= MUSY_VERSION_CHECK(2, 0, 0)
+        volume = d + ((u16)ptr[vhigh] << 16);
+#else
         volume = d + (ptr[vhigh] << 16);
+#endif
       } else {
         volume = ptr[vhigh] << 16;
       }
diff --git a/src/musyx/runtime/synthvoice.c b/src/musyx/runtime/synthvoice.c
index 739f91e2..d2641af4 100644
--- a/src/musyx/runtime/synthvoice.c
+++ b/src/musyx/runtime/synthvoice.c
@@ -194,9 +194,11 @@ static void voiceInitPrioSort() {
   voicePrioSortRootListRoot = 0xffff;
 }
 
-void voiceRemovePriority(const SYNTH_VOICE* svoice) {
-  SYNTH_VOICELIST* vps = &voicePrioSortVoices[svoice->id & 0xFF]; // r31
-  SYNTH_ROOTLIST* rps;                                            // r30
+void voiceRemovePriority(SYNTH_VOICE* svoice) {
+  SYNTH_VOICELIST* vps; // r31
+  SYNTH_ROOTLIST* rps;  // r30
+
+  vps = &voicePrioSortVoices[svoice->id & 0xFF];
   if (vps->user != 1) {
     return;
   }
@@ -294,7 +296,7 @@ void voiceFree(SYNTH_VOICE* svoice) {
   u32 i;                // r29
   SYNTH_VOICELIST* sfv; // r30
   i = 1;
-  MUSY_ASSERT(svoice->id!=0xFFFFFFFF);
+  MUSY_ASSERT(svoice->id != 0xFFFFFFFF);
   macMakeInactive(svoice, MAC_STATE_STOPPED);
   voiceRemovePriority(svoice);
   svoice->addr = NULL;