I live in a house and have a door bell installed with a button placed outside the gate. Lately the unit has been working sporadically and I often (though not all the time) have heard a kind of buzzing/crackling sound from it. I thought it was some kind of short.

Today I installed a new unit and although the unit works I get the same buzzing/crackling noise from this unit as well. What could it be?

Assuming this is a Thai-style wired mains bell with 220V at the bell-push I would be investigating if there's damp or creatures in the bell-push.

Did you replace the outdoor switch also? Ours corroded over badly and ended up replacing the whole set.

Thank you both. I actually had the same thoughts even though being totally inept at "handy work" . Will change it out and see what happens.

I had a problem with mine as did my neighbours, turned out the underground wiring had corroded, simple solution was to replace it with a wireless bell! Easier than digging up the drive!

I had a problem with mine as did my neighbours, turned out the underground wiring had corroded, simple solution was to replace it with a wireless bell! Easier than digging up the drive!

Any way that I can check that before I buy a new buttom or do I need an electrician?

I had a problem with mine as did my neighbours, turned out the underground wiring had corroded, simple solution was to replace it with a wireless bell! Easier than digging up the drive!

Any way that I can check that before I buy a new buttom or do I need an electrician?

Just disconnect the button at the far end, put a choc-bloc or some tape over the bare ends for safety. If the fizzing noise continues it's not the button.