Hi . First off I want to say I don't know too much about PC's. Anyway I just got a new PC (with Win 7) and it came with realtek HD audio sound. I hooked up the monitor to the graphics card (ATI Radeon 5770) with an HDMI cable. Everything worked fine for a few days until I tried to hookup a turtle beach x11 xbox 360 headset to play with some friends. I couldn't get the mic working and resorted to using my webcam to talk. I turned on my PC the next day and all my audio is gone. My headset, my monitor's in-built speakers, Ipod headphones there is no sound for any of them. I looked around and my PC still thinks it's playing music (the green bars are moving) and Realtek HD Audio Manager says everythings is fine. I tried to update the drivers via the device manager and they says its up to date. I'm lost as for what to do next. Any help would be great. Let me know if you need more info. Thanks.