I had the same problem. Sounded like a jack hammer when I ran the disposal. It was my bad. I neglected to pull out the plastic tab you punch out for the dishwasher. Did not feel it when I put my hand in. I took the unit off and turned upside down and gave it a quick shake. It fell right out and the noise is gone. This was mentioned in the directions and I should have paid better attention.

Take a magnet on a rod, with electrical tape wrap on it(just one wrap) and try to see if a small spoon or something fell in to it. My wedding ring fell in to mine, this is how I got it out, talk about chewed up. Please ensure to unplug it before do this!!