Appliance Repair Questions? Ask a Technician for Answers ASAP
I am not sure what you mean by "turning by itself". When I throw the switch, the disposal makes a noise similar to that of a normal disposal and I can see the plate you show spinning.
My choice here is to have go after an Insinkerator warranty without the receipt or get a replacement. I am not interested in anything that I can't repair myself. Do you know how I contact Insinkerator regarding warranty work?