I have my blu ray connected to my Denon AVR-5800 receiver via an optical cable, but I cannot get DD5.1, just dolby surround. I get DD with everything else, all TV channels, etc, but not with the NSZ-GT1. I have tried all types of settings, and then even reset to factory defaults but still no DD. I am missing something obvious, but could anyone tell me what it might be? Thanks.