Scientists finally solve mystery of buzzing sound 4% of world's population can hear

A perplexing phenomenon known as 'The Hum' has seemingly been figured out by a team of researchers, 50 years since it was first documented.

In the 1970s, the Bristol Evening Post received letter after letter from locals about their trouble with an unexplained sonic disturbance in the area.

Suggestions of a warehouse's immense industrial fan system being the cause were quickly rubbished, and so the mystery persisted.

Fellow UK-based coastal communities like Southampton, Swansea and Plymouth began suffering from the sound too, as did individuals in London, before reports of cases across the US emerged in the 1990s.

Residents of Canada, Australia, New Zealand, South Africa and Norway have all encountered this low-frequency buzzing sound in their ears as well, which has finally led to a scientific study.

Four percent of the world's population can hear The Hum (Schöning/ullstein bild via Getty Images)

As many as four percent of the world's population now live with The Hum; for some it is irritably manageable, for others the ringing brings physical discomfort into their lives.

Acoustic pollution, technology, traffic, naturally-occurring environmental sounds (like wind blowing through landscapes or ocean waves meeting the shore) and even alien activity have all been bandied around as proposed triggers.

In 2024, the BBC even dramatised the phenomenon in a series titled The Listeners - starring Rebecca Hall, Prasanna Puwanarajah, Ollie West and Amr Waked.

Per Science Daily, a new journal put together by the Norwegian University of Science and Technology professor Markus Drexl made some fascinating conclusions after investigating 28 people from Germany with the hearing issue.

Drexl and his team tested whether those who can hear it have either exceptional low-frequency perception or measurable sounds produced inside their ears.

"We know that there are people who hear low-frequency sounds that can actually be measured, even if other people don't hear them," said the professor.

"But it's not so easy to find the source of these sound waves, because it's a struggle to localise low-frequency sounds."

In the end, having considered the two hypotheses, the studiers decided that many of The Hum's so-called victims are experiencing low-frequency tinnitus.

"Based on our results, although we haven't ruled out cases of physical external sound sources, we suggest that subjective tinnitus in the low-frequency range is often the cause of hearing pulsations of low-frequency sound perceptions," noted Drexl.

A tiny portion of The Hum's hearers may boast unusually sensitive low-frequency hearing, though.

Symptoms of tinnitus

Tinnitus is a hearing condition where noise appears in one or both ears, or the head, when no external sound is apparent.

Symptoms include faint ringing or humming down the ear canal, or hissing, whistling and roaring.

Dave Grohl of the Foo Fighters, Brian Johnson of AC/DC, Pete Townshend of The Who, and the late Ozzy Osbourne of Black Sabbath all suffered from tinnitus due to their unique career paths as rockstars.