The microwave is a 10 year old GE spacemaker, model JVM1650WH01. It is part of the range/oven/microwave combo. so it is mounted underneath the cabinet, and hanging above the range/oven
Everything on the microwave works. However, from time to time, there is a loud vibrating noise coming from behind the control panel. This only happens when I am using the microwave to heat up stuff. The vent fan works fine without any vibrating noise.
When I put a little downward pressure on the microwave, the vibrating noise goes away. If I apply a little upward pressure by pushing on the bottom of the microwave, the vibrating noise gets stronger.