I thought I'd see if any of the computer nerds, er experts

had some advice on how to fix my sound problems.
If I play sound on any source, video, mp3's etc the sound stutters. Even during the Windows start up. Sometimes when watching video it improves after a while.
I've run RegSupreme and fixed errors and reinstalled MediaPlayer. According to Device Manager there are no installation issues with the sound card.
So I'm stumped. Anyone got some advice for me?
Cheers.