Bizarre problem with online play

When I try to play online I can only host one match before the game temporarily freezes and then disconnects me from live. If I try to join a game I just get disconnected right then and there.

It's weird because I'm not connected to XBOX live, yet the game hasn't caught up. I have to wait a while for the disconnected from live message to pop up and then reconnect.

The game works fine after reconnecting to live.

I've port forwarded, and my NAT is listed as open. This happens whether the computer is on or not, and I'm not sure if this is a problem with the game or console because VF5 is pretty much the only game I play online.

What's going on here?

 

Test: eliminate the router.
Plug the xbox directly into the cable/dsl modem.
Restart the modem (in this order)
wait however long it takes for the modem to be connected to the internet
connect to xbl and play several games

if problem persists -> problem is with your modem or with your connection. contact the provider and see if there are any problems in your area.

if problem doesn't persist -> problem is with the router. Maybe a setting; maybe broken. Make sure UPNP is on (if it has that option) and that you have the latest firmware. (check the manufacturer's site)

beyond that it could be xbl acting up or even your xbox...

Good Luck

 

Updating the firmware did the trick. Thanks for suggesting that.