I just had the same problem. My computer was working a few days ago but all of a sudden the sound stopped working. I can't hear out of the internal speaker or headphones. The system says that there is no problem with the speakers or anything, it detects sound and doesn't show any errors. For some reason the little blue/orange mute button stopped changing colour, which happened at the same time... but the button still works because the volume icon on the taskbar changes correctly. I have tried to disbale and uninstall drivers and all that business but nothing seems to work as yet. Any more ideas? The computer is out of warranty so HP won't help me.