Yesterday my headphones didn't work. I posted here, and someone suggested that I click Device Manager > Sound > Uninstall. Then reboot my machine, and everything worked. So, yesterday, BOTH the headphones and the regular speakers worked fine. Today, without making any changes whatsoever, my regular speakers don't work, but the headphones work fine. So, I went through the same steps: Device Manager > Sound > Uninstall. Then reboot my machine. it still doesn't work. Any idea what I can try next? This was working perfectly fine yesterday.