A disposal that hums but will not turn usually has a jammed impeller or a stuck reset button. One that leaks under the sink is more often a loose mounting ring or a failed seal at the dishwasher inlet than a fault in the unit itself. A disposal that trips the reset weekly is nearing the end of its motor life.
Before calling, turn off the switch and never reach into the disposal by hand. A jam can sometimes be cleared from above with an offset wrench in the bottom center hole, if the unit has one.
Burning smell, a leak that keeps returning, or a jam that will not clear are reasons to stop and call. Smart Pro Plumbers connects Chula Vista, CA homeowners with a plumber who diagnoses, repairs, and replaces garbage disposals sized to the sink and how the kitchen gets used. Reach the referral line at (844) 898-0295.