I am thinking about buying A Harman Kardon AVR 132 so I can connect 5.1 speakers to my Mac. I will be using the optical out of my Mac. I just wanted to check, will this receiver decode surround sound from a Mac. Also will this receiver up-mix to 5.1? Basically will the receiver be ok with all the sound output a mac will through at it. I am not worried about it always being true surround sound.