A board will not work, then not work, etc. If and when it fails, it fails. I would check for faulty connections. I need to know the code# of your machine. On some models there was a relay. If you are flipping your switch on and off you are causing the relay points to open and close, until they 'unstick'
I have only replaced 3 idler/protection boards since 2001. Not a common problem. CHECK THE RELAY (if your machineis that model). REMOVE THE COVER AND CLEAN THE CONTACTS. Whalla your fixed.