No "Stereo Mix" option (yes, ive checked disabled devices)

I have no idea what to do. I even tried updating all my audio driver stuff, but the only one it allowed me to update was that ATI HDMI Output, and I don't even know what that is because I've never used it. There was another driver (the High Definition Audio Device) but when I tried updating that it warned me that my system may become unstable, so I didn't.

so far, no one has been able to help me with this on any website or forum