Microwave makes a crackling, arcing, or popping sound inside the cavity during cooking.

Immediate action: Stop the microwave and unplug it if you see sparks or hear arcing.

• Remove metal objects: Ensure no metal utensils, foil, or containers are inside. Only use microwave-safe cookware.
• Clean the cavity: Wipe the interior with a mild detergent solution to remove grease and food splatter, especially near the waveguide cover (usually a small mica or plastic panel on the side wall).
• Inspect waveguide cover: If the cover is burnt, cracked, or has holes, it must be replaced. Do not operate the microwave without this cover.
• Touch-up paint: If the cavity enamel is chipped exposing bare metal, use microwave-safe cavity touch-up paint to cover small areas after cleaning and drying.

Persistent arcing after cleaning and replacing the waveguide cover may indicate deeper damage to the waveguide or magnetron and should be checked by a technician.