I recently bought 4 a6060 spektrum servos. i installed them in my model tech magic and in my pre flight check the left aileron flutters. it moves up and down when i hold the stick in one spot. i was using an ar600 spektrum reciever and thought that my reciever was may be bad. i switched to my ar7000 and the rudder does the same thing. are these badservos or something else? any help would be awesome.</p>