Unit lag

[jh1990]

When playing on LAN with another person we get some serious unit lag. I will click to move a unit and it takes about 5 to 6 seconds to finally move. As soon as one of us disconnects everything moves along fine. We have tried everything, connecting straight to the internet, connecting directly with cat5 cable, using a combo of three different PCs. Nothing seems to work, almost unplayable right now. Need some help. Thanks