RE: help on power box champion rrs
This may or may not be related to your problem, but the powerbox feeds a current limited amount of voltage to the receiver, I am not certain, but I think it is around 1 ampere. If servos are connected directly to the receiver and draw more than that, it can brown out the receiver. The fix has traditionally been to use the signal wire only from the receiver to the servo, and scavenge the voltage from a free output on the power box.