It could be the drivers for the untold OS. Your best bet is to try a reboot then if this is Windows (some use Linux) then System Restore to when it worked.
Here's what happens:
I turn on the computer, works fine, no viruses.
However, I tryed listening to a YouTube video, no sound. Volume was all the way up, volume is up on mixer.
Checked the sound devices, there was no playback devices. The speaker that attaches to the monitor is up, the blue light is on. The cord for the speakers is plugged into the computer, I can't fix it. Input Monitor volume cannot be changed on Volume Mixer because it's grayed out. Please help!
P.S. Cannot figure which to put this in, please move if in the wrong place admin