Problem with all videos except DTS & DD


Hi, first of all some details about my system

I have Mac mini for playing most of the downloaded movies

Marantz SR6007 receiver

Sony PS3

Pioneer BDP-140

SVS PB-13

Adelaide Ascension Summoner floor standing Spks

My problem is, when I play any video with DTS or DD or DTS-HD from any of my sources, I get very good and perfect sound but when I play any video with 5.1 AAC, all the dialogues comes from left channel and centre channel becomes left channel. I tried to play different videos from different sources i.e. mac mini, BD Player or PS3 but the result is same. I think something is to be done with my Marantz receiver.

Has any one came across this problem? Any help or suggestions????