I've recently purchased this game, but when I tried to play it, I found that the sound is borked. It plays a bit, but then gets caught in an infinite loop somewhere halfway. Due to this, both music and speech are inaudible and you miss more than half of the conversation.
I've tried messing with the compatability mode and the sound settings through DXDiag, but none of it worked.

Have you tried updating your sound drivers???

I had the same problem, or something very similar. I solved it by running JackOrlando.exe in Windows 98/Me compatibility mode.
This was on a laptop with Windows XP, Intel GM45 chipset and Realtek HDA audio hardware.