I've gone through two adapters and endless hours of trying to get 5.1 audio to my receiver via hdmi or with optical and I can't seem to get it to work. Well, let me correct myself. I got it to work in osX but whenever I start vlc the audio goes from 7.1 to some random configuration where it only comes out of the side speaker. I can't seem to get dts or ac3 to consistently output from vlc to my receiver. Honestly if I have to use the optical I don't care I just want it to work. I got normal audio but not dts or ac3 to work with osX. Then using bootcamp and windows 7 I got the vlc to output only some ac3 via the optical to the receiver. I never got hdmi sound to output in anything other than 2 channel in windows. Anyway if anyone can spread some light on how to accomplish this it would be greatly appreciated at the moment I am using http://www.kanexlive.com/v2 which they claim will pass uncompressed 5.1/7.1 as well as dts and ac3 through. This entire thing is frustrating. Their technical support is laughable.