I'm having a problem getting Dolby Digital sound from my DVD player. I have the Samsung hooked to the Pioneer via digital coaxial cable. When playing a movie, the digital label shows up on my AVR. However, the signal is only digital, not Dolby Digital which is a separate label. I've checked the DVD disc menu to make sure it is DD 5.1 mode. The AVR is on the DVD/LD input source. I have a DVD 5.1 input source, but when I switch to it I get no sound. Any ideas on what I'm doing wrong here?