I had a similar issue, and found this topic on Google when trying to find a solution. Here's what I've found:
Symptoms: Sound stuttering / crackling / skipping / static when loading websites, or for some people, with other heavy network usage such as torrenting. Often grows worse with time since the last reboot. Can be noticable and immediate, or can gradually appear over time.
Technical Explanation: High DPC latency. Usually an issue with a driver.
Cause: In my case -- COMODO Firewall. Known issue with 3.8 and up (3.10 currently) on Vista or Win7 RC. As of this post the devs have been aware of it for several months but have not yet been able to fix it.
Topic on their forums:
http://forums.comodo.com/firewall_bu...-t34562.0.html Solution: Downgrade to COMODO 3.5, or uninstall.
3.5 available here:
http://forums.comodo.com/feedbackcom...-t31145.0.html
This might not be the reason for your issue, but this post is meant to help other Googlers too.
If you don't use COMODO, the cause is still probably something causing high DPC latency. In that case, get the tool mentioned here to help you figure out what it may be:
https://forums.comodo.com/firewall_b...4996#msg304996