I just got a powermac G5 1.6 and have had a panasonic 5.1 channell Dolby Digital System hooked up to my plasma. I was hoping to rid myself of my dvd player and just use the DVI on the G5 for a dvd player with better quality. I notice that when I hook up the toslink cable to my system I only get 2 channell PCM. Even when playing a DVD with the 5.1 channell selected. Is there and option to click or program to install that will give me 5.1?