I have an Insinkerator disposal. It runs fine for a day or two then will stop and hum. If I'm there (not my wife) I turn it off and back on and it runs. When it stops it makes a soft noise, like metal clacking. When my wife lets the disposer breaker kick out, I use the fly wheel wrench and turn the fly wheel. It's never hard to turn. More mushy than anything else. One half "easy" turn does it. I reset the breaker and it runs fine for a few days. It always makes a noise when it shuts off and this noise started when the problem started.