I recently upgraded to blu ray and purchased a Sony BDP-S580. I have it running audio via coax to my Sony DA555ES receiver and noticed over the weekend that certain movies produce a significant amount of audio distortion, specifically in dialogue. This only happens when the disc is encoded with DTS Master HD audio (anything in Dolby sounds fine). I read somwhere that while my receiver can process DTS, it (because it is a little older) cannot process DTS Master HD. Could that be the case? When I go into the audio settings on the blu ray player my only option is to downmix to PCM, and thus I lose DTS. If what I read is correct, is there any possible way to fix this without the purchase of a newer receiver? I am still fairly new to home theater systems, so please excuse me if some of my terminology is incorrect.