I have an AVR630 connected via optical to a NAD T533 DVD player. I watched Open Range last night and decided to select DTS on the DVD's audio menu. What happened is that the AVR630 is still in Dolby Digital and only two speakers are working. I had to reset the DVD to Dolby 5.1, no biggie but I still wonder why the DTS on the AVR won't light up if the disc sound was selected to DTS. I tried to switch via remote but won't. Any tips? Also, the DVD player has an option for 48 and 96 khz. Which one should I select? Thanks. I know I can google all this for the answer but I have spent 20 minutes so far and can't find it. THanks again.