Ive got an asus a7v600 and im trying to run surround sound out of the coax digital out. It runs into a surround reciever. I selected 5.1 in all the relevant places, and i am using a surround audio file (from microsoft wmp 10 site). However, im only getting the front channels. When i select 5.1 from the soundmax control panel, it tells me to restart, and when i do, its reset back to stereo. Please help.