Microwave makes a popping sound and light flickers when starting, but then continues to run.

Safety first: Unplug the microwave and do not continue using it until inspected.

Step-by-step checks:

• 1. Inspect cavity: Look for burnt food, especially near the waveguide cover and corners. Clean thoroughly.
• 2. Check for metal: Ensure no metal trim on dishes or utensils is used.
• 3. Inspect lamp area: If the popping seems to come from the lamp, check the bulb and socket for looseness or arcing marks and replace if needed.
• 4. Technician inspection: If popping persists, a technician should inspect internal wiring and high-voltage connections for loose or damaged parts.