That has happened to me on 2 different pc's, on the hp, it was because i had plugged the speaker plug in the mic jack on the back(how stupid of me!), the eMachines was hooked up right and still no sound. I am curious to know tha fix for this problem too. Hopefully somebody smarter than me knows how to fix it.
I'm not sure what I did, but I don't have sound anymore...it's not on mute either. I think I might have adjusted something in My Computer, but can't figure it out. I did a sound test and they are working? Any suggestions?
Thanks.. Irene

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