I'm having serious network-related problem when playing Spiral Knights. Certain aspects of the games suddenly stops working for long periods of time, and it happens constantly. Despite the problems persisting over fifteen minutes the game does never actually disconnect. The game works fine on other networks, so I know it's not my computer.
I have 10mbps download, 0.7mbps upload, and three or two bars of ping in-game.
I have tried port forwarding (47624 through 47634) and setting up a DMZ.
What doesn't work: