When starting microwave, there is a quick "buzz" that last about a second and then the buzzing stops. When it stops, it kind of sounds like a contact closed. The sound resembles a contact solenoid buzzing to close and then finally closing. Most of the time, it only does it at startup and then heats just fine. On rare occasions, the buzz cycle repeats itself every few seconds with no heat. I stop the micro, restart it and then it is fine - it only does the buzz one time. The buzz happens at EVERY startup, but the repeat buzzing is rare. The repeat buzzing is, however, starting to increase and happen more often.

The micro starts just fine, buzzes, and then heats just fine. So, other than the buzz, everything works perfect.

Any ideas?

Thanks in advance.