Xbox 360 sync with zune problems. can anyone help?

heres the deal. whenever i sync my xbox 360 to my zune or connect it to my computer it doesnt doesn't transfer/sync all of my music or movies. it sometimes doesnt even show some of my albums or artists. like i have The Drought is Over: Grand Closing on my zune and when i sync it to my xbox 360 it doesnt even come up. so i made a playlist with just that album. so when i went to find it with my xbox i found it...but i wounldnt let me play the songs for some reason. does anybody know whats goin on and or how to fix it? Thanks