To state the obvious: you probably should obtain a new KOP router. The part is a Linksys WRT160N, available for $99 (or, for a limited time, $75, from
Newegg; I personally strongly suggest ordering from them, as their shipping is FAST).
To say any more would be speculation; it is possible that another network is interfering.
Something else to check: I seem to remember there being an issue with sticking your router up against a metal member of your robot. If you move it a little further away from the frame, does it perform better?