halo 4 campaign issues

Hello everybody. halo 4 is great, but on the levels “Foreunner” and the level after infinity (forgot the name) it loads to 56 or 30 and then skips to 0, after a while it says that one or more players do not have the downloadable content. can someone please help, some forums say that I have to clear may data cache on the xbox360 but I am not going to risk it unless it is the only option left