Mine too but with different symptoms. Mine does a normal startup but when when the transmitter stick is moved foward (throttle) the tank dies, when moved backwards the sound level drops to zero and no movement is observed. Lights and turret functions are ok RX13 board, changed crystals, changed transmitter and receiver batteries, changed transmitter, same story. Have not done a detailed inspection of the board yet but that will be done soon Sounds like the main board to me but what do you all think?