If you have another player ie. CD player or borrow another CD/DVD player from a friend. If it doesnt happen then its your receiver.

Did you ever plug that lower ports with those foam bungs. I found the Silver line sounded/imaged better with the lower ports plugged. The bass on those puppies at high level was a little overbearing the mids and highs.
Just try it out and see which you like it. It pretty much a personal preference from every individual.

Saturn

http://www.quadloft.com/hometheater- new HT