I know, I know, it's been asked. A lot. But it seems my problem's fairly unique.
First, I'm running Creative SBS 560 5.1 speakers through a 24-bit Live! card. Yes, ancient, I know, but they've done the job for the last four years...until about a month ago.
I turned on my computer and they emitted a loud pop--louder than usual (yeah, if I left the speakers on when turning off/on the computer they popped) and static started coming out of the left rear. This was almost unnoticeable, getting gradually worse (and spreading to all the speakers) until I was forced to salvage some real old speakers and go back to 2.1. The noise occurs through just the SBS speakers, and through either the on-board card or the Creative PCI one. It doesn't occur when I plug the SBS speakers into my laptop.
I knew it was bound to happen eventually--I got those speakers direct from creative for $40 back in '05 or so. Still though, it makes me
Muting/unmuting/disabling various card combinations and inputs/outputs has done nothing, as well.
Maybe your psu is getting ready to go south,what you might try,,unplug your 'puter from the wall ,turn it off and on several times,don't be in a hurry if it works,fine, if not,see beginning is this input...)
Unfortunately all of those have been done recently--my computer's closed, it's been moved from on top of my desk to below, the speakers have been moved...the only thing left is that the EMI shielding in the speakers themselves is failing. That would be my guess, if it wasn't for the fact that in the exact same position, with my tower on, all of them (center/sub, front, and rear) work when plugged into my netbook.
Definitely a weird issue, but seeing as how I paid basically <$10/year for their use I think I'll just get a new set when I have the money, switch to my onboard card, and use AC3 Decoder for audio upmix. Now if only they'd add the ability to upmix to 8 channels instead of just six...
Just exchanged Philips speakers for an older pair of Sony speakers I had upstairs. No interference now. This works.
My issue wound up being grounding issues with the 'puter itself. The speakers mentioned in the thread are now connected to my living room 'puter with its own grounding/shielding issues (noises came from the 2.1 I had connected before getting a 3-way 1/8" splitter), and the buzzing is minimal.