I was playing Harry Potter and Half Blood Prince on 7.1 audio track. I have the analog and optical connections set up. The optical connects through a dacMagic and has a very poor performance, as though 5 channels are missing in fact. The stereo isnt much better. When I played the stereo audio track it was much better. However that track includes description for the Blind, so isnt what I want. I have the Blu ray player set to PCM and Downmix stereo. Is there any other setting I should consider?