diff --git a/include/z64audio.h b/include/z64audio.h
index 023fece0a6..ee145c9d80 100644
--- a/include/z64audio.h
+++ b/include/z64audio.h
@@ -496,8 +496,9 @@ typedef struct {
     /* 0x18 */ SequenceLayer* wantedParentLayer;
     /* 0x1C */ NoteAttributes attributes;
     /* 0x40 */ AdsrState adsr;
-    // Majora's Mask suggests this struct contains portamento, vibratoState
-} NotePlaybackState; // size = 0x60
+    /* 0x60 */ Portamento portamento;
+    /* 0x6C */ VibratoState vibratoState;
+} NotePlaybackState; // size = 0x88
 
 typedef struct {
     struct {
@@ -539,10 +540,8 @@ typedef struct Note {
     /* 0x00 */ AudioListItem listItem;
     /* 0x10 */ NoteSynthesisState synthesisState;
     /* 0x30 */ NotePlaybackState playbackState;
-    /* 0x90 */ Portamento portamento;
-    /* 0x9C */ VibratoState vibratoState;
     /* 0xB8 */ char unk_B8[0x4];
-    /* 0xBC */ u32 unk_BC;
+    /* 0xBC */ u32 startSamplePos; // initial position/index to start processing s16 samples
     /* 0xC0 */ NoteSubEu noteSubEu;
 } Note; // size = 0xE0
 
diff --git a/src/code/audio_effects.c b/src/code/audio_effects.c
index 84fde3a305..9a6d1884a4 100644
--- a/src/code/audio_effects.c
+++ b/src/code/audio_effects.c
@@ -174,11 +174,11 @@ f32 Audio_GetVibratoFreqScale(VibratoState* vib) {
 }
 
 void Audio_NoteVibratoUpdate(Note* note) {
-    if (note->portamento.mode != 0) {
-        note->playbackState.portamentoFreqScale = Audio_GetPortamentoFreqScale(&note->portamento);
+    if (note->playbackState.portamento.mode != 0) {
+        note->playbackState.portamentoFreqScale = Audio_GetPortamentoFreqScale(&note->playbackState.portamento);
     }
-    if (note->vibratoState.active) {
-        note->playbackState.vibratoFreqScale = Audio_GetVibratoFreqScale(&note->vibratoState);
+    if (note->playbackState.vibratoState.active) {
+        note->playbackState.vibratoFreqScale = Audio_GetVibratoFreqScale(&note->playbackState.vibratoState);
     }
 }
 
@@ -188,7 +188,7 @@ void Audio_NoteVibratoInit(Note* note) {
 
     note->playbackState.vibratoFreqScale = 1.0f;
 
-    vib = &note->vibratoState;
+    vib = &note->playbackState.vibratoState;
 
     vib->active = 1;
     vib->time = 0;
@@ -212,7 +212,7 @@ void Audio_NoteVibratoInit(Note* note) {
 
 void Audio_NotePortamentoInit(Note* note) {
     note->playbackState.portamentoFreqScale = 1.0f;
-    note->portamento = note->playbackState.parentLayer->portamento;
+    note->playbackState.portamento = note->playbackState.parentLayer->portamento;
 }
 
 void Audio_AdsrInit(AdsrState* adsr, AdsrEnvelope* envelope, s16* volOut) {
diff --git a/src/code/audio_playback.c b/src/code/audio_playback.c
index fb9f77e817..02c9422d68 100644
--- a/src/code/audio_playback.c
+++ b/src/code/audio_playback.c
@@ -926,11 +926,11 @@ void Audio_NoteInitAll(void) {
         note->playbackState.attributes.velocity = 0.0f;
         note->playbackState.adsrVolScaleUnused = 0;
         note->playbackState.adsr.action.asByte = 0;
-        note->vibratoState.active = 0;
-        note->portamento.cur = 0;
-        note->portamento.speed = 0;
+        note->playbackState.vibratoState.active = 0;
+        note->playbackState.portamento.cur = 0;
+        note->playbackState.portamento.speed = 0;
         note->playbackState.stereoHeadsetEffects = false;
-        note->unk_BC = 0;
+        note->startSamplePos = 0;
         note->synthesisState.synthesisBuffers = AudioHeap_AllocDmaMemory(&gAudioContext.miscPool, 0x1E0);
     }
 }
diff --git a/src/code/audio_synthesis.c b/src/code/audio_synthesis.c
index 58135c3356..d50d1f4d48 100644
--- a/src/code/audio_synthesis.c
+++ b/src/code/audio_synthesis.c
@@ -745,7 +745,7 @@ Acmd* AudioSynth_ProcessNote(s32 noteIndex, NoteSubEu* noteSubEu, NoteSynthesisS
     if (noteSubEu->bitField0.needsInit == true) {
         flags = A_INIT;
         synthState->restart = 0;
-        synthState->samplePosInt = note->unk_BC;
+        synthState->samplePosInt = note->startSamplePos;
         synthState->samplePosFrac = 0;
         synthState->curVolLeft = 0;
         synthState->curVolRight = 0;