Age of Empires 2 expansion multiplayer problem

I'm having a problem with age of empires 2 expansion multiplayer over
the internet.
Here is the story:

When I host a game I check that the correct ports in my router are open
then I have 2 people from outside my network try to connect. They make
it into the lobby and are able to chat with eachother BUT I (the host)
cannot see their chat and they cannot see mine before they are dropped
from the room afetr about 1 minute. Then If I close the game I am unable
to browse but am able to ping websites and use programs like msn
messenger.

When I connect to a game outside my network the same thing happens
except they do not experience the loss of browsing.

We are all running Vista home 32bit (as far as I know) I use a belkin
wireless G router.

Any suggestions? I'd really like to resolve this problem, I've never
encountered it before and I've been playing aoe2 online for years.

Note: This started a few weeks ago, before it started everything worked
fine and several of us played the game without any problems.

Also, sometimes they can see my game but cannot connect and I turned
off my firewall to ensure it was not blocking connections.


--
Pieter15