Hello, my son and I are building our first plane (Simple Cub). We are having issues with the servo motors (ES08AII). We plugged them into the receiver (an AR620), and let them zero. Then we mounted them in the plane and were testing the controls when they started moving back and forth aggressively for 5-6 seconds and then quit. We were no longer able to control them (no movement). We had a couple extra, and tried again, being careful to zero them before hooking up the control rod and gluing them in (to zero we plugged them into the receiver with no arm attached and powered them up and left them find zero. then attached the arm without moving the motor). Both worked initially, but then started moving aggressively and appeared to burn out. The only other thing I noticed is it seemed on the last one It started acting up when I moved the receiver around. I am wondering if the receiver was loosing the feedback signal (or it was erratic) and that initiated the damage. I ordered some new servo motors and a new receiver, but if anyone has any insight I would appreciate it. I'd rather not end up with more damaged servo motors. Thanks!