The answer to 'surge protector making buzzing noise' is that a buzzing sound from a surge protector is usually a sign of an issue with the internal components. This can indicate the surge protector is failing and no longer providing effective protection for your electronics.
Common causes include old or faulty capacitors, loose connections, or damage to the internal circuitry. The buzzing noise is often a sign the surge protector is nearing the end of its lifespan and should be replaced to ensure your valuable electronics are properly protected.