I had the same, it was the pedal!
I was able to verify it was the pedal without buying a new one by removing it, taking the side off, cleaning the contacts (don't bother touching the metal prongs, just the carbon strips) and refitting. There is adjustment in the idle position, I moved it slightly so it doesn't sit back on the same idle position and locked the adjustment. It was giving that fault pretty much every drive, it hasn't done it in three months now so it looks like that was def. the problem.