My AMD HDMI Output is greyed out and static

I can silence the noise lowering volume on the Stereo Mix High Definition Audio Codec. However, my AMD HDMI Output is greyed out and static, or as I understand from other complainers; NOT PLUGGED IN. What can I do to solve this problem. It is a problem for when I open the Stereo Mix High Depfinition Audio Codec, a shrieking noise leaves me depth, and it eats the volume all up.

My system: Windows 7

HP  Lop Top - A6 - 3400M - APU with Quad Core Radeon HD Graphics - 6.0GB RAM -  AMD Radeon HD 6520

Thanks in advance for your help.