Lose connection to host once lobby reaches 5+ players

[content404]

I've been having connection problems since the beginning, I can't think of any other possible fixes. I am able to join most automatch games, only customs games give me trouble. If I join a lobby with 1-4 people in it then I also have no connection problems. Once 5 or more players join the lobby I lost connection to the host.

forever.log: http://pastebin.com/rF9zUtde

In the log above, I have hosted a custom game to check that the ports match up. I have set port 6874 with uPnP enabled. The second portion of the log is when I experienced the problem described above, once 6 players joined the lobby I lost connection with the host.

I have attempted using port forwarding without uPnP and well as switching up the ports with/without uPnP, no change either way. When I enable DMZ hosting I am unable to log in to FAF, as soon as I disable DMZ hosting I can log in without problems. I have attempted enabling DMZ hosting with FAF running, no change. I use ZoneAlarm firewall & antivirus and have given FAF and SupCom FA full permissions.

I'm completely out of ideas, any help would be appreciated.

[Xinnony]

Try without ZoneAlarm

[content404]

It's related but I haven't found a pattern, disabling the firewall works sometimes but not all. When disabling does work, I can re-enable it in game without having problems.