Home theater question??

by deluca_9 - 4/9/12 1:54 PM

Hi everybody, I just recently purchased a Sony DVD Home Theater System that includes the receiver, 1 center speaker, 2 front speakers, 2 rear speakers, and a subwoofer. The system is the Sony DAV HDZ278. It sounds very good in my 10 X 10 room, but I just have a problem getting Dolby Digital 5.1 Sound. The system itself is a DVD player with HDMI, Component, and RCA outputs, and it also has a digital optical input. I plugged the HDMI cable from my receiver to my tv, and I have a digital optical plugged from my receiver to my tv. The digital optical cable gives me sound for my Xbox 360, cable box, etc. However, when I play DVD's on the receiver I get dolby digital 5.1 sound, it even says so on the display. When I play anything else aside from the DVD player, it says Dolby Pro Logic II on the display of the receiver. So when I play my Xbox 360 or watch tv on my HD Cable box it only shows Dolby Pro Logic II sound. I have tried several games on the Xbox 360, so its not the game's fault. ANy suggestions from anyone on how to get Dolby Digital 5.1 Sound for everything I play?