With large control surfaces and analog servos vibration itself can create the movement. Can you hold an aileron with the engine running and keep it from moving? Vibration with a glow engine is usually caused from an out of balance prop. Glitching usually shows up with just a couple control surfaces moving. With all of them moving it can be a bad RX glitching from a bad pot. Just some ideas to check out. Bypass the battery switch just by plugging the battery plug directly into any open port will tell you if it is a loose wire in the switch.