Just found this on the EA site -
Q: Sometimes when I match up to someone ( In a head to head game type.. i.e. Quick ranked, unranked, FIWC, online league, Interactive league, etc ) the screen shows both sides as my favourite team, and I'm only able to change the team if I'm on the home side. Eventually, the session ends and I'm booted from the session. Why does this happen?
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A: When you match up with someone through our centralized server, you then establish a direct peer to peer connection with your opponent. This p2p connection establishment process needs to navigate any firewalls, routers, and other network devices between you and the opponent. This process is difficult and is highly dependant on the type of routers used by both parties, and how they have configured their port forwarding and routers. The best solution to this problem is to make sure you have a UPnP capable/Xbox live compatible router, and that you open the right ports to your ps3 or xbox. I believe there is a sticky about how to do this properly. If not, I'll see if we can get one up.
Side note: You may have noticed that this is much more frequent in head to head matches than it is in online team play or clubs matches. This is because online team play and club matches connect to an EA hosted game server, and do not need any type of port demangling or other fancy process to establish a connection. ( Since the server is on a dedicated public internet ip address (no NAT) and the right ports are opened on the server side. )
I think you both need to do the port forwarding thing.
Take a look here and see if it helps:
http://forums.electronicarts.co.uk/...x-360/360824-guide-connect-fifa-ps3-xbox.html
Good luck