This is slightly embarrassing for me to admit, but since I am not an A/V geek I think it is ok.
When I first moved to Philadelphia I took it upon myself to purchase a home theater system. I went with a Sony Dream system. It was easy to setup; within minutes I had a surround sound setup.
A few months after the purchase I noticed that the sound wasn't as surround as it should have been. In fact, the back speakers weren't emitting any sound at all. I fiddled with the speaker wires and came to the realization that the speakers themselves, and the wires, were fine.
Yet surround sound eluded me. I tried a variety of other tactics, including but not limited to sacrificing to goat to Odin, but nothing helped. I even thought of calling Glenn (my audio equipment guru) and ask his opinion, but I didn't.
Fast forward to this evening; I just popped in the Empire Strikes Back DVD and looked down at the DVD player's remote. What's this button called 'DVD Setup' do I wonder?
I pushed the button and a menu with a variety of options appeared on the screen. One of the options presented to me was 'Speakers,' and so I selected it. Turns out my center speaker and the two rear speakers were turned off from some reason in the software of the DVD player. I turned them all on, and like magic I was able to watch the Empire Strikes Back in surround sound.