Bristol hum: Council investigates mystery noise
Bristol City Council is looking into reports that a mysterious low-frequency noise which has plagued some residents of the city for decades is back.
Since New Year, social media reports have surfaced of a low pitched hum, while others in the same area cannot hear it.
Bristol City Council tried to measure the noise in April 1980 after scores of complaints, but the hum continues.
"It was definitely humming away last night," Sheila Masey told the BBC.
Mrs Masey has lived in Staple Hill, north of Bristol, for 34 years. For the last 20 she has heard a "low rumbly hum".
"It's not every night, but there are certain nights when you think: 'Crikey, here we go'.
"I wouldn't say it wakes me up but if I can't drop off to sleep and it happens to be there, then I'm always conscious of it."
She had thought it might be linked to factories in Filton.
"It can get on your nerves at times but as it's not all the time, you just accept it."
Jake, from Downend, wrote on BBC Points West's Facebook page: "I hear it about 80% of nights ... It's changed pitch lately, it seems like an electrical buzz... It's the not knowing what it actually is that drives me mental."
Complaints about low frequency noise date back to the 1970s but most people do not hear it and some are sceptical about whether it exists at all.
'Occasionally receive complaints'
It is one of many "hums" worldwide and there have been many theories about its cause. Last year the Bristol Post reported that French researchers believed it was caused by waves vibrating on the ocean floor.
A Bristol City Council spokesman said: "We do occasionally receive complaints of hums from across the city.
"We are currently investigating to see if there is any evidence to suggest the existence of a noise problem and whether any action can be taken. "
Lisa, from Clifton, heard the Hum at night, in 2013 and 2014, when she had her second child.
"I thought it was me because I was very 'sinusy'," she said, adding she was "dumbfounded" to learn it was a local phenomenon.
She described it as like a "really softly beaten giant drum".
"It's easy to become, for periods, a little bit obsessed with the hum. You focus on it and, in the middle of the night, you find it difficult to screen out other noises."