I get only varying strange static sounds. Sound was working great before. Best I can say is that I installed a new case fan. At one point after I turned the comp on, it suddenly shut off after I opened up google chrome. I turn it back on, no sound, only static. I tried uninstalling and reinstalling drivers. No effect. Also, I get constant messages that I plug and unplug a device into the audio jack, even though I'm doing no such thing. I tried plugging in headphones directly to the phone jack on the mobo thinking it might just be the speakers. Nope. Same thing. There is clearly a problem. Is this fixable?
Try uninstalling the drivers and re-installing. If that does not cure it and you have not made any other changes to the OS (installed new software and codecs), then it sounds like the sound chip got damaged somehow. They are supposed to be sensitive to ESD.