High-pitched whistling or hissing noise from the lid during pressure cooking.

Safety first: Keep clear of the steam path; escaping steam can cause burns.

• Observe behavior: A brief hiss during pressure buildup can be normal, but continuous loud whistling suggests a restriction.
• Clean steam components: After cooling, remove and clean the steam release valve, anti-block shield, and surrounding lid area.
• Inspect gasket: Check the sealing ring for early signs of hardening or flattening; replace if more than 12–18 months old or visibly worn.

If whistling remains loud and continuous even with clean components and a new gasket, the steam release assembly may need replacement.