I did a forum search and didn't see this problem, and apologize if it's been discussed.
I own a Samsung DLP 50" HLM507W. It was one of the first year DLPs.
The problem I have is that my XBOX runs really dark. I have the internal XBOX settings at widescreen and 480/720/1080 compatabiltity, and have it plugged into the 480 component jack. Even with brightness set at 100, it's much darker than on my other TV, almost pitch black in some areas. When I run it through the non component jacks, it is much brighter, but the resolution is awful. HDTV and DVDs look great, however.
Any help or ideas would be appreciated. I've tested other XBOXs on it to make sure it wasn't my system.