I had this problem - audio kept cutting out every time CPU usage was high, and the computer kept acting like I was unplugging my speakers. As recommended in that thread, I uninstalled the Realtek software that had come with the mobo drivers, and that fixed it for a while. But now the problem is back - the audio cuts out frequently, or doesn't work at all. As far as I can tell, the problems started after I installed Java, although that might be a coincidence.
I've updated the Windows sound drivers, but that didn't fix it. Is there anything else I can try?