diff --git a/src/audio/external.c b/src/audio/external.c
index 7b554b1a..bd189ee9 100644
--- a/src/audio/external.c
+++ b/src/audio/external.c
@@ -7,6 +7,7 @@
 #include "external.h"
 #include "playback.h"
 #include "synthesis.h"
+#include "game/debug.h"
 #include "game/main.h"
 #include "game/level_update.h"
 #include "game/object_list_processor.h"
@@ -696,6 +697,7 @@ struct SPTask *create_next_audio_frame_task(void) {
  * Called from threads: thread5_game_loop
  */
 void play_sound(s32 soundBits, f32 *pos) {
+    assert(((soundBits & SOUNDARGS_MASK_SOUNDID) >> SOUNDARGS_SHIFT_SOUNDID) != 0xff, "Sfx tables do not support a sound id of 0xff!");
     sSoundRequests[sSoundRequestCount].soundBits = soundBits;
     sSoundRequests[sSoundRequestCount].position = pos;
     sSoundRequestCount++;
diff --git a/src/audio/seqplayer.c b/src/audio/seqplayer.c
index b64b8b9c..d4e9a546 100644
--- a/src/audio/seqplayer.c
+++ b/src/audio/seqplayer.c
@@ -1620,11 +1620,11 @@ void sequence_channel_process_script(struct SequenceChannel *seqChannel) {
                     case 0xc5: // chan_dynsetdyntable
                         if (value != -1) {
 #if defined(VERSION_EU) || defined(VERSION_SH)
-                            seqData = (*seqChannel->dynTable)[value];
+                            seqData = (*seqChannel->dynTable)[(u8) value];
                             sp38 = (u16)((seqData[0] << 8) + seqData[1]);
                             seqChannel->dynTable = (void *) (seqPlayer->seqData + sp38);
 #else
-                            sp5A = (u16)((((*seqChannel->dynTable)[value])[0] << 8) + (((*seqChannel->dynTable)[value])[1]));
+                            sp5A = (u16)((((*seqChannel->dynTable)[(u8) value])[0] << 8) + (((*seqChannel->dynTable)[(u8) value])[1]));
                             seqChannel->dynTable = (void *) (seqPlayer->seqData + sp5A);
 #endif
                         }
@@ -1893,7 +1893,7 @@ void sequence_channel_process_script(struct SequenceChannel *seqChannel) {
                                 eu_stubbed_printf_0("Audio:Track: CTBLCALL Macro Level Over Error!\n");
                             }
 #endif
-                            seqData = (*seqChannel->dynTable)[value];
+                            seqData = (*seqChannel->dynTable)[(u8) value];
 #if defined(VERSION_EU) || defined(VERSION_SH)
                             state->stack[state->depth++] = state->pc;
                             sp38 = (u16)((seqData[0] << 8) + seqData[1]);
@@ -2011,11 +2011,11 @@ void sequence_channel_process_script(struct SequenceChannel *seqChannel) {
                         break;
 
                     case 0xb5:
-                        seqChannel->unkC8 = *(u16 *) (*seqChannel->dynTable)[value];
+                        seqChannel->unkC8 = *(u16 *) (*seqChannel->dynTable)[(u8) value];
                         break;
 
                     case 0xb6:
-                        value = (*seqChannel->dynTable)[0][value];
+                        value = (*seqChannel->dynTable)[0][(u8) value];
                         break;
 #endif
                 }
@@ -2045,7 +2045,7 @@ void sequence_channel_process_script(struct SequenceChannel *seqChannel) {
 
                         case 0x98:
                             if (value != -1 && seq_channel_set_layer(seqChannel, loBits) != -1) {
-                                seqData = (*seqChannel->dynTable)[value];
+                                seqData = (*seqChannel->dynTable)[(u8) value];
                                 sp5A = ((seqData[0] << 8) + seqData[1]);
                                 seqChannel->layers[loBits]->scriptState.pc = seqPlayer->seqData + sp5A;
                             }
@@ -2121,7 +2121,7 @@ void sequence_channel_process_script(struct SequenceChannel *seqChannel) {
 
                     case 0xb0: // chan_dynsetlayer
                         if (value != -1 && seq_channel_set_layer(seqChannel, loBits) != -1) {
-                            seqData = (*seqChannel->dynTable)[value];
+                            seqData = (*seqChannel->dynTable)[(u8) value];
                             sp5A = ((seqData[0] << 8) + seqData[1]);
                             seqChannel->layers[loBits]->scriptState.pc = seqPlayer->seqData + sp5A;
                         }