|"flickering on and off on mute"|
Do you mean the sound is stuttering? That's not usually due to a driver issue, it could be you have some crappy program running in the background. If you want to try reinstalling the driver, that's fine, but we can't help unless you post the make/model of your motherboard or make/model of your sound chip or make/model of your system (if it's an OEM). AC'97 is a generic term.