Intermittent, follow the power through from the plug, are happy that the wiring is good? Next you could try: open the mixer as to get the bowl out. Lay the mixer on its end and if you look carefully through the black guard you can see there is an adjustment screw just inside on the far side on the top part of the mixer, turn it a little at a time (with the power not connected) and see if that helps. If that fails maybe the on off switch on the mixer but I have never gone there.
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