Safety first: Keep clear of the steam path. Do not cover the valve.

Check valve position: Confirm the valve is set to the correct pressure position as indicated on the lid.
Stop and inspect: If noise is excessive, cancel the program and allow pressure to drop. Then remove and inspect the valve.
Clean valve seat: Rinse the valve and its seat to remove food particles. Ensure correct reassembly.
Replace valve gasket: If the valve gasket is hardened or cracked, replace the steam release valve assembly.

Loud hissing or whistling noise from lid during pressure cooking.

Possible Causes