Product review (1 stars): Loud Buzzing Caused by a Design Problem
I installed the disposal and it made a loud buzzing noise. After a call to KitchenAid, they sent a repairman out to look at the problem. He isolated the buzzing to the red plastic pieces that goes around the outside. They were loose and vibrating on the internal metal part of the disposal. He removed the plastic pieces, reinstalled it, and the buzzing stopped but it was still louder than my 20 year old Kenmore that it was replacing. He told me the buzzing was a design problem and he could not fix it. I packed it up and shipped it back to Amazon for a refund.