The most common issue I see with this is some setting in the MIXER or the owner accepted a driver from Windows Update.
If this is a recent failure, use System Restore to roll back to when it worked.
Bob
I have a HP DV7-1232NR laptop PC. I am having a sound issue that completely has me stumped. I get audio sound upon computer startup and shutdown and all audio controls are working, i can even listen to CDs. My problem is that when I;m trying to listen to an MP3 file or watch a video on Youtube I have no sound at all. Somebody please help me!! Thanks

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