You have lost connection to the session

[Eldrick_Silver]

 I keep getting this message when trying to join my friends' games. sometimes it works sometimes it doesn't. I'm sure my internet connection is fine as I can play my other multiplayer games without issue.

I've reset my tcp/ip stack, internet connection, restarted the game and origin and my computer but still no dice. what other troubleshooting step can I perform to check this? it's frustrating as hell.

Thanks