Fix Oil Ocean Music Bug
From Sonic Retro
There is a bug that occurs when you input the 14 Continues cheat, which causes the game to play Oil Ocean Zone's music forever.
The cause of this can be found in the CheckCheats function:
move.b #SndID_ContinueJingle&$7F,d0 ; Play the continue jingle jsrto (PlayMusic).l, JmpTo_PlayMusic
The issue here is that the game is sending an invalid SMPS sound command: valid sound commands start at $80, yet this command is actually $3F. The sound driver doesn't handle this properly, causing it to malfunction, and prevent itself from playing any new sounds or music.
To fix this, remove the '&$7F'. This changes the command to $BF, which is handled properly.