IT’S a mysterious buzz that can drive people to the brink of madness.

For those that hear it, ‘The Hum’ can cause sleepless nights, stress and nosebleeds and is described as a relentless “kind of torture” with no explanation.

Now after years of speculation the drone was caused by everything from submarines to gas pipes or mating fish, scientists believe they have found the reason for the unexplained noise.

“The hum is the least understood part of Earth’s oscillations,” scientists Fabrice Ardhuin, Lucia Gualtieri and Eleonore Stutzmann wrote in Geophysical Research Letters.

The trio have undertaken detailed computer modelling of ocean, wind and sea currents and believe the “microseismic activity, recorded everywhere on Earth, is largely due to ocean waves.”

Oceanographer Mr Ardhuin told Live Science the pressure of the waves on the sea-floor causes the earth to vibrate like a bell and creates a sound that is heard more by some than others.

“I think our result is an important step in the transformation of mysterious noise into an understood signal,” Mr Ardhuin said. It’s thought a better understanding of the how the hum is produced could help scientist better understand the Earth’s interior.

The findings will be a relief to many who have complained of the hum since the 1960s. Those who hear it, known as ‘hummers’, were originally dismissed by doctors as suffering from tinnitus. However it’s been described as a “kind of torture” that sounds like a “diesel car idling in the distance” and has been attributed to everything from military bases to microwaves.

Those that hear it complain of losing sleep, stress and even being driven to suicide or the brink of madness. One specific case of the “Bristol hum” in the UK led to 800 people writing to the local paper complaining about the noise with some saying they had suffered nosebleeds and headaches.

One man even founded a Low Frequency Noise Sufferers’ Association for those plagued by the noise that reportedly had interest from sufferers in New Zealand, Canada and New Mexico.