I know there are probably other posts addressing this issue, but the fact that there is even a post at all, means there is a serious problem with EA Server disruption during MP gameplay. If I put the resources into buying packs and I put the time into playing the game, I would expect not to be disconnected from the EA Server at Wave 11 or while I'm in the middle of a Wave. It is pretty frustrating to spend 16-23 minutes on completing a map, just to get a stupid message that says I've lost connection to the server, yadda, yadda, yadda.
It also does not make for good game partners if they think you left the game, which if you're the host and you get disconnected, restarts the Wave. I don't want excuses about how many people are playing that's overloading the server, just fix the problem. Don't write checks you can't cash.