Today i've bought and installed Crysis 2 Maximun edition on steam, all work fine except for multiplayer. Every time I try to play i get this message after 4-5 minutes of game (the same thing happen also in menu) "The connection to your opponent has been lost..." .

I'm an online gamer and i've a lot of games like BF3, Css, Left for dead and other no one give me this problem.

I've also googled a lot to figure out this prob but without success.

My IP is on DMZ, I don't have active Firewall or Antivirus.

On Crysis NAT is on Moderate.

Someone could help me?