I’m having the same problem. It may have something to do with the sound card. In my case I use a Dell laptop and as I understand it my system does not have an internal sound card. The sounds are handle via software which I believe is causing the problem. I’ve been searching the forums to see if anyone else has used an external sound card with a laptop to see if it corrects the problem.
Here’s the original site for the sound http://blender.instinctive.de/downloads/release/docs/audiosequencer.html
Also this from Alexander explains the issue at the bottom of the article http://osdir.com/ml/video.blender.devel/2003-09/msg00098.html
Correct me if this is wrong: I think it may have something to do with the sound card internal clock, in my case there isn’t one which is why the problem exists. So I was searching to see if anyone has used an external sound card that corrected the problem. So far I have not.
Also I believe the sound card needs to be OpenGl compatible. But I’m guessing on all of this. Hopefully someone more tech savvy can set me straight.