Hmm, seems when I listen to the game's music, it sounds different from the soundtrack...
Either they didn't do it right, or there's something wrong with my computer's audio drivers?
Every other kind of sound plays normally.
Yes, it was my driver. I fixed it by turning the "Hardware Sound Acceleration Level" down to "Basic acceleration". Turning it to "No acceleration" completely distorts the music and sound, while Basic completely fixes it.
Edit:
Hahaha, make sure you turn this thing back up after you're finished with whatever cavestory stuff you're doing.
Respawning in Blockland makes a horrid sound with this on Basic...