I'd use System Restore (it's a feature in most Windows) to the day before when it worked.
Bob
In the middle of streaming an online local concert via HDMI to our TV, the sound quit. it came back a couple times, then quit fully. and now I can only get sound out of the headphone jacks in my Dell laptop (with Windows Vista), whether I'm trying a DVD or music files already in the machine. I have searched your forums, gone thru the control panel/sound, the Windows Media Player options/sound/speaker settings and everything says it's working fine. It's not muted. do I need to restore? might speakers on a 2-year old machine just quit? the built-in sound is "IDT High Definition Audio Codec." thanks much.

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