ONE: Have you scanned your computer for viruses?
TWO: Have you scanned your computer for Hijackers and other malicious programs?
THREE: Have you scanned your computer for hidden / invisible Key Loggers or other similar programs like that?
Because, I've only experience that particular sound every now and then in DD and BD when I try to perform a game function that the game doesn't like or if I teleport somewhere.
If your game is making that sound while you are totally idle and not doing a single thing in the game, and you are not touching your keyboard or mouse, something is running in the background causing it, whether malicious or not.
LASTLY: Welcome to the forum.
Tsel <img src="/ubbthreads/images/graemlins/wave.gif" alt="" />