i.e: some times me and a friend have to restart the xbox/modems so many times before we can connect… both nats are open and its never been an issue until lately…
then it takes a while to find a match in doubles… both have cable connections!
What about when you go in alone…? it may just be your two connections dont like each other for some reason. Your both open nat yes but sometimes IP difference can do this too, take ages to find games stick you in a game of firefight alone ( just the two of you )etc.
Yes that did affect thins even in a game with me and my friend, we both had people round our house for a halo fest and 4 players on each team, either he or I would have pulled host and we have had no problmes before but during last week we had load failures and games that would start then kick one of us within mins. We just had to wait it out, but I personally havent had this since last week.
You could try re-downloading your profile and clearing your HDD cache, I was told to do that the first time I had the issue with the server the week before last and it worked. She also said that not regularly clearing your cache can cause lag ? which I never knew.