I was a plumber in my past life and rarely have seen people use their disposals correctly. People seem to think anything can go down the disposal without turning the water on. First off coffee grounds and vegetable peels should be thrown in the trash NEVER down the drain.These items tend to stick to the inside walls of your pipes choking off the opening. Second your water should be turned on before you turn on the disposal & not shut off for a good minute after you run the disposal. Once a month it'seems also a good idea to fill your sink or sinks if you have a double bowl and flush out the pipes.