Microwave is very loud during operation, with a deep humming, buzzing, or rattling noise.

Warning: Loud buzzing from the high-voltage area can indicate a failing magnetron or transformer. Unplug the unit before inspection.

• Isolate noise source: Listen carefully to determine if the noise is from the top, side, or bottom. Remove the glass tray and run briefly to see if the noise changes (do not run empty for more than a few seconds).
• Check for loose items: Ensure no utensils or racks are vibrating inside. Verify the turntable and support ring are seated correctly.
• Fan and mounting check (advanced): A technician can remove the cover and tighten loose screws on the transformer, magnetron, and fan assembly, and replace any noisy motors.
• Stop use if burning smell: If noise is accompanied by a burning odor, unplug immediately and seek service.