lost buffers/lost frames

[gresseball]

I am playing a file on an other computer in my little network of 3 pc's.
This goes relatively fine for about a minute or 2 when the picture suddenly freezes and soud stops. then after a couple of secs the sound is back, but the picture is still frozen. when the picture starts "moving" again, you can se the coding/blocks moving abaout.
Is the routers speed that is to slow or is it somthing else? The speed is only 54MBPS, but playing a divX movi over the net shold go easy, shouldent it?
One of the computers is wireless, the other is "wired".

Espen.