I'm still having said problem with a friend of mine (also in quick matches it seems, though that is at random).
1:I'm connected through cable.
2:Every time.
4: PC.
5:Router setup is with enabled uPnP and port forwarded through the ports that i found somewhere else for DA:I, but forwarding shouldn't have been needed with uPnP activated.
6:We have managed to play together before, but that was through a proxy (another friend hosted).
Another note I have setup a lan network through hamachi and given it priority and we still can't connect, this is not a port issue or uPnP, there is something serverside stopping us.