High-pitched squealing, buzzing, or humming noise from the cooker during operation.

Safety first: Unplug the cooker before opening the housing.

• Check placement: Ensure the cooker is on a stable, level surface. Thin countertops can amplify vibration.
• Inspect heating plate mounting: Tighten any loose screws securing the heating plate and internal brackets.
• Secure transformer: On the control board, gently press on the small transformer (if present) to see if the noise changes. If so, a technician can apply non-conductive varnish or replace the board.
• Monitor function: If the noise is minor and the cooker operates normally, it may be safe to continue use. If the noise is accompanied by burning smell or malfunction, discontinue use and seek service.