Well, to start with, you should probably stop scratching your ear with that rusty nail...
Heh - just kidding. See if you have the latest drivers for your sound card, and that you have the latest version of DirectX. That's the best place to start. Nobody will be able to tell you much more until you post your system specs.
"The obvious mathematical breakthrough would be development of an easy way to factor large prime numbers."
- Bill Gates