Hello All, My Panzer III has the rx-18 board All connections are good. Tank runs in right direction. Turrns correctly. No speed control though. At stop though I hear a whirring like the motors are trying to start. Trim will not get rid of it. No variable speed. Just one speed. Bad board ? Wires are connected correctly according to diagram. This was a non smoke sound version. Everthing from motors to transmitter is new.

Thanks for any assistance.

David