Hi, I've got an issue with Vista Ultimate when playing a DVD movie in Media Centre. I cannot change the volume! My mainboard is an A-open and I am using the SPDIFF output into a Sony 5.1 system. When I alter the volume within Media Centre the blue box appears in the top right corner of the screen and the volume output via my Sony system changes as I would expect - Except when playing a DVD... THe volume doesnt change regardless of if the on screen level is 0 or full? Can anybody help?