Hd Mixer My Volume Control Is Not Working...Mixer Not Found?

My volume Control is not working...Mixer not found? - hd mixer

ok .... I have some for the conversion of my HD video camera ... such as converting AVI files to HD ..... But after the conversion had no sound (i new when I went on YouTube), said just click on the volume control does not install the active mixers ...: S j 'So I searched the net and said that the current and Windows audio service.msx, but show that your house still does not work ... I noe my computer mixer, but I donno what the problem plzzz help

Thank you very much