Splinter Cell: Chaos Theory SP Demo problem.

[Prince of China]

I just got the demo from the link in the Chaos Theory thread in the general gaming thread. There is a problem with my sound. The sound is fine for a while but when I hear my first in-game conversation, the sounds and music of the game become high-pitched and goes extremely fast.
How do I fix this?

 

[furiousV]

drivers? dont use EAX (if available). speaker configs. stop other programs that use sounds bofore playing.
corrupt installation?