Got this for Xmas so my son and I could actually play a game together, on-screen, full cooperative campaign, etc. Well, I've been messing with it for 30 minutes now and we can't play two player!! Every time I select campaign mode, split-screen it gives me a "Two players must be signed in to play split screen". I'm signed in to Xbox live, both controllers are lit and ready, so what does it mean we need to be signed in??

I can't find a place to create an in-game character or anything.

Anyone????