speedmistro,
As long as the radio passes a range check you don't have anything to worry about. As it was said above, your transmitter is too close to the receiver antenna. Let me guess, when you turn on the receiver and transmitter the transmitter is leaning on the plane?? Or right next to it??? What's happening is that the transmitter sitting that close to the receiver is simply "overpowering" the receiver and causing the twitching. As soon as you move a bit away it stops. Nothing to worry about as long as the system range checks ok.

Hope this helps

Ken