Hey, I'm having Xbox Live problems...

I can sign into xbox live fine(I connect by using an Ethernet cable from the console to my laptop, if that helps) but suddenly whenever I click "Xbox Live" from the Multiplayer page, a message appears on the screen that says, "Downloading game settings..." This literally appears for only a second, and whenever I try to find a match on Free-For-All it always says "Waiting for 3 More Players." The strange thing is that I was able to play successfully just three hours before this first occurred. I checked, and my connection is perfectly fine. Does anyone else know what to do to get into a match? Thanks in advance...

P.S. I also tried playing another game, to see if it was only COD4 that was having problems but I couldn't find any players for that game either.