Realtek AC 97 - the two black and silver speakers, made by Logitech? Has a subwoofer?
I own those too - great speakers for their price.
Anyhow, I ran Trend Micro's Housecall, and found a little piece of spyware that I had not detected otherwise. Upon removal, everything became much smoother. When I was infected, the paging light, the red one, was always on, or look like a strobe light. Now it's back to normal =D