Whenever I try to join a certain friend's fireteam, the game tells me that my online permissions may have changed, or that I lost connection. This only happens with one friend, or any fireteam that he's already in. If he leaves, I can join the fireteam he was in, and then he can join on me, but no matter what, the game kicks me back to the "Press X to play" screen when I try to join on him. This is the only friend that this has happened to me too. What's going on?