Pu-Li-Ru-La (PSX) - Background music (CD Audio/BGM) is missing

Hello, I found an issue with the MiSTer PlayStation core. Game: Pu-Li-Ru-La (PlayStation) Verified Redump dump. Issue: The game runs correctly and all sound effects are present, but the background music is completely missing during gameplay. What I tested: BIN/CUE image → Same issue. CHD image → Same issue. Original CD loaded using the new physical CD/DVD drive support → Same issue. In all three cases, only the sound effects are heard; the background music never plays. Expected behavior: Background music and sound effects should both play correctly. Reference: The exact same disc/image works correctly on a real PlayStation, where both the music and sound effects play normally. If you need any additional tests or logs, I'd be happy to help. Thank you for your work on the PSX core.