Unusual Lag

When my cousins plays on halo 2 anniversary mm he hits REALLY bad lag. He lives near to me and his internet speed is 20mb/s mine is slower than his.
I do not lag nowehere near as much as he however he has faster internet what is going on. He also does not lag on any other game only this game. We can play customs alright its just mm. An tips for him

> 2533274883108544;1:
> When my cousins plays on halo 2 anniversary mm he hits REALLY bad lag. He lives near to me and his internet speed is 20mb/s mine is slower than his.
> I do not lag nowehere near as much as he however he has faster internet what is going on. He also does not lag on any other game only this game. We can play customs alright its just mm. An tips for him

BUMP

Figure out what nat type he has on his network and open it if possible.