Unit wouldn't start. Cycled on off switch a few times it started. 2 weeks later wouldn't start again. Same drill still wouldn't start. Unplugged for a few minutes plugged back in and on/off switch lit program buttons flickered, then nothing. Replace the controller 1 week later acted just like last exercise. Do you think it's the on/off swith, door latch microswitch or something else like a power supply?