Music sounds like singing with helium

I am having a problem when playing music on my computer and downloading music. When it plays it sounds very fast and like they sucked on some helium. I tried goin in my control panel but that didnt work. I think its something deeper. No matter where i get music to play from it sounds like chipmunks on speed. I have a COMPAQ- DESKPRO ("yuk") with win2000, a cd writer, too. How do i get my music to sound normal again?

thank you,
gilena