How do i fix my call of duty connection?

EVERY time i play call of duty it will alwasy let me join no problem but when im in the middle of a game a little white connection thing will pop up and flash and say connection interrupted? It always says my connection is at full bars so i dont know what it could be, i have opened up port forwarding to port TCP [80] UDP [88, 3074] Any one have any sudjestions? thanks alot