Had a call earlier from a chap I've worked for in the past, his CU [renewed around 12 years ago] and meter is sited in a cupboard under the stairs. The meter fitter was 'on site' and concerned about a buzzing sound in the aforementioned cupboard. He thought it could be dangerous and also thought there was a loose connection... So the chap I know put him on the phone and I explained that it could just be an MCB as some do make a bit of noise, I said could he switch them off one at a time and see when the buzzing stops ? No he said, not allowed to do that, so I suggested he fit the meter and I would check out the buzzing on the way home, ok he said.
So I called in on the way home and stuck my head in the cupboard, worked out within about 5 seconds that the offending sound was the doorbell transformer, totally harmless- it's also on it's own labelled circuit so not difficult to work out. And would you believe the old meter was still there, "Too risky" to fit the new one apparently. So the customer has now told his supplier that he won't be having a Smart meter now.
So I called in on the way home and stuck my head in the cupboard, worked out within about 5 seconds that the offending sound was the doorbell transformer, totally harmless- it's also on it's own labelled circuit so not difficult to work out. And would you believe the old meter was still there, "Too risky" to fit the new one apparently. So the customer has now told his supplier that he won't be having a Smart meter now.