Network bridge Moderate NAT. Possible to open?

So basically I have my 360 in my room running a network bridge from my laptop so I can connect to live. My other xbox works fine but the one with the bridge won't connect to some game lobbies that have a decent amount of people in it. Can this be solved or should I just buy a wireless adapter?

EDIT: alright so it turns out the NAT isn't working right on the wireless 360 either. I have all of the ports open but for some reason it still won't work. I hate when this happens...