diff --git a/soh/soh/Enhancements/audio/AudioCollection.cpp b/soh/soh/Enhancements/audio/AudioCollection.cpp
index 26494a7d5..3d988c9be 100644
--- a/soh/soh/Enhancements/audio/AudioCollection.cpp
+++ b/soh/soh/Enhancements/audio/AudioCollection.cpp
@@ -261,6 +261,10 @@ extern "C" void AudioCollection_AddToCollection(char *otrPath, uint16_t seqNum)
     AudioCollection::Instance->AddToCollection(otrPath, seqNum);
 }
 
+bool AudioCollection::HasSequenceNum(uint16_t seqId) {
+    return sequenceMap.contains(seqId);
+}
+
 const char* AudioCollection::GetSequenceName(uint16_t seqId) {
     auto seqIt = sequenceMap.find(seqId);
     if (seqIt != sequenceMap.end()) {
@@ -269,6 +273,18 @@ const char* AudioCollection::GetSequenceName(uint16_t seqId) {
     return nullptr;
 }
 
+size_t AudioCollection::SequenceMapSize() {
+    return sequenceMap.size();
+}
+
 extern "C" const char* AudioCollection_GetSequenceName(uint16_t seqId) {
     return AudioCollection::Instance->GetSequenceName(seqId);
+}
+
+extern "C" bool AudioCollection_HasSequenceNum(uint16_t seqId) {
+    return AudioCollection::Instance->HasSequenceNum(seqId);
+}
+
+extern "C" size_t AudioCollection_SequenceMapSize() {
+    return AudioCollection::Instance->SequenceMapSize();
 }
\ No newline at end of file
diff --git a/soh/soh/Enhancements/audio/AudioCollection.h b/soh/soh/Enhancements/audio/AudioCollection.h
index 6b7a78fa0..75247793b 100644
--- a/soh/soh/Enhancements/audio/AudioCollection.h
+++ b/soh/soh/Enhancements/audio/AudioCollection.h
@@ -58,8 +58,12 @@ class AudioCollection {
         uint16_t GetReplacementSequence(uint16_t seqId);
         void InitializeShufflePool();
         const char* GetSequenceName(uint16_t seqId);
+        bool HasSequenceNum(uint16_t seqId);
+        size_t SequenceMapSize();
 };
 #else
 void AudioCollection_AddToCollection(char *otrPath, uint16_t seqNum);
 const char* AudioCollection_GetSequenceName(uint16_t seqId);
+bool AudioCollection_HasSequenceNum(uint16_t seqId);
+size_t AudioCollection_SequenceMapSize();
 #endif
\ No newline at end of file
diff --git a/soh/src/code/audio_load.c b/soh/src/code/audio_load.c
index eb788fd0c..583ce84fe 100644
--- a/soh/src/code/audio_load.c
+++ b/soh/src/code/audio_load.c
@@ -1346,7 +1346,7 @@ void AudioLoad_Init(void* heap, size_t heapSize) {
     int customSeqListSize = 0;
     char** seqList = ResourceMgr_ListFiles("audio/sequences*", &seqListSize);
     char** customSeqList = ResourceMgr_ListFiles("custom/music/*", &customSeqListSize);
-    sequenceMapSize = (size_t)(seqListSize + customSeqListSize);
+    sequenceMapSize = (size_t)(AudioCollection_SequenceMapSize() + customSeqListSize); 
     sequenceMap = malloc(sequenceMapSize * sizeof(char*));
     gAudioContext.seqLoadStatus = malloc(sequenceMapSize * sizeof(char*));
 
@@ -1366,16 +1366,27 @@ void AudioLoad_Init(void* heap, size_t heapSize) {
     int startingSeqNum = MAX_AUTHENTIC_SEQID; // 109 is the highest vanilla sequence
     qsort(customSeqList, customSeqListSize, sizeof(char*), strcmp_sort);
 
+    // Because AudioCollection's sequenceMap actually has more than sequences (including instruments from 130-135 and sfx in the 2000s, 6000s, 10000s, 14000s, 18000s, and 26000s),
+    // it's better here to keep track of the next empty seqNum in AudioCollection instead of just skipping past the instruments at 130 with a higher MAX_AUTHENTIC_SEQID,
+    // especially if those others could be added to in the future. However, this really needs to be streamlined with specific ranges in AudioCollection for types, or unifying
+    // AudioCollection and the various maps in here
+    int seqNum = startingSeqNum;
+
     for (size_t i = startingSeqNum; i < startingSeqNum + customSeqListSize; i++) {
+        // ensure that what would be the next sequence number is actually unassigned in AudioCollection
+        while (AudioCollection_HasSequenceNum(seqNum)) {
+            seqNum++;
+        }
         int j = i - startingSeqNum;
-        AudioCollection_AddToCollection(customSeqList[j], i);
+        AudioCollection_AddToCollection(customSeqList[j], seqNum);
         SequenceData sDat = ResourceMgr_LoadSeqByName(customSeqList[j]);
-        sDat.seqNumber = i;
+        sDat.seqNumber = seqNum;
 
         char* str = malloc(strlen(customSeqList[j]) + 1);
         strcpy(str, customSeqList[j]);
 
         sequenceMap[sDat.seqNumber] = str;
+        seqNum++;
     }
 
     free(customSeqList);