Microwave makes crackling, popping, or arcing noises inside the cavity during operation; visible sparks may be seen.

Safety first: Stop the microwave immediately and unplug it.

• Remove metal objects: Ensure no metal utensils, foil, or twist ties are inside.
• Clean thoroughly: Wipe the interior with a mild detergent solution, paying special attention to the area around the waveguide cover.
• Inspect waveguide cover: Replace if burnt, cracked, or has holes.
• Touch up paint: If small rust spots or chipped paint are present, sand lightly and apply microwave-safe cavity paint as per manufacturer guidance.