I have a Pioneer Elite 45tx. I have my xbox and dvd player set-up to via digital connection to get 5.1 surround. I've tried countless times to get my digital cable box (timewarner pioneer) to work via the digital cable (co-ax). I get no sound. I've looked through the cable box set-up menu, but nothing about Dolby or DTS can be found. The Dolby Sign is on the front of the cable box.