Sound is weird!!!

Hi, I recently purchased a AA1 and the sound in XP just started getting wierd. It was working fine, but something seems screwy now. When is boots up, the winxp opening sound plays fine. When I go to an mp3, that plays fine, but when I go to the taskbar, and click on the slider, the "ding" noise is super quiet. Also if I go to "sound" under "contol panel" and i click on the system sounds, they are all very quiet except for windows opening and windows closing, and windows log on, and log off - everything with the word "windows" in it, is loud - but all other notification are very low - but all my volumes are turned up!! I noticed it in yahoo instant messenger when i was talking to someone and he was extremely quiet. Really weird...Someone please heeeelp!!