The answer to 'panel upgrade making buzzing noise' is that a buzzing noise coming from your electrical panel is often a sign of a problem that requires professional attention. This can be caused by loose connections, overloaded circuits, or issues with the panel itself.
Some common symptoms include a buzzing or humming sound, flickering lights, or breakers tripping frequently. While you can try to troubleshoot minor issues, it's best to have a licensed electrician inspect the panel and make any necessary repairs. Attempting to fix a panel issue yourself can be dangerous and may even violate local electrical codes.