You can tune the range potentiometer. Take the ESC cover off the thing, pick the wax out of the round, white potentiometer, and have someone handle the remote while you screw the thing until you find the optimal range.
also, it's been floating around other forums that you can replace resistor R20(location:near the xtal base) with a 2.2K ohm resistor and it'll boost the output signal of the controller.
not sure about the truth of it.. but a resistor swap in the controller is simple enough and can be reversed easily if it doesnt work.
Linear Mode
