I have a problem with my FF6 xs 35Mhz suddenly with antenna fully closed and moving just a couple of meters away from receiver there is servo movement if I just slowly shake the radio, I have tried two different channels 76 and 88 and 3 different recievers 76 small gws and 2 x 138DF same response but more movement on one of the 138 DF where shall I start looking ???