I would do a good range check, engine running, to see if you have a radio interference problem. If there is no noticable glitching in the servos go to full power and check again, if it only is noticable at full throttle I would take the prop off and balance it to see if that could be your problem. I know there are a lot of people out there that dont belive it is necesary to balance a prop but I have seen first hand what a prop that is badly out of balance can do the end result was a H-9 cap 232 sport that was shaken to pieces.