[problems with multiplayer]

having alot of lag issues but i dont lag on any other game talked to xbox and they cant seem to find prob anyone got a suggestion i have even tried a direct connect to modem i get same prob.

[getting kicked off multi player]

when i try to join a match it says lost connection to one or more players and then kicks me back to single player. i trouble shot with xbox and we found nothing wrong my router is open and i have no prob with any other game. any one got an idea?