Yes. This is normal. IH rice cookers use electromagnetic induction to heat the inner pot directly. During Keep Warm mode, the IH heating system may switch on and off intermittently to maintain the temperature, which can produce a slight buzzing or sizzling sound.

Residual steam or moisture may also come into contact with the rice or inner pot, causing occasional popping or sizzling sounds.

This does not affect food quality or safety. However, if the sound is unusually loud or is accompanied by a burnt smell, scorch marks, overheating, or circuit tripping, stop using the rice cooker and have it inspected.