I had a similar problem with a Harrier90. Could not get the twitching to stop using a Hitec receiver with JR125MG servos. Replaced the JR servos with Hitec and flew the plane. Nothing wrong on the first two flights and then with my brother at the controls the plane violently banked right with no warning. He managed to get it straightened out only to have it bank again and hit the ground. He flys a WH Edge 540T, Obsession 3D and Funtana 90, so he knows how to fly. Firewall torn out but no other meaningful damage. Was discussing the crash with the owner of the hobby store and he asked it I was running a Spectra module in the Optic 6 transmitter. I said yes and he gave me a fixed channel module to use. He said that when they were flying combat and switched to the switchable frequency modules they started loosing planes, quickly. Went back to the fixed modules and everything returned to normal. I sent my Spectra module back to hitec for testing but I don't think I'll fly with it anymore. The plane has numerous flights since the repair with no adverse servo twitching or unexplanable events of any kink. I'll probably put the spectra module on ebay.