The mysterious sound known as The Hum has been reported worldwide for decades, yet its source often remains impossible to find. Researchers tested whether people who hear it have exceptional low-frequency hearing or measurable sounds produced inside their ears, but neither explanation fit most participants. The strongest possibility is that many cases involve low-frequency tinnitus, even though the sound seems completely external.

The mysterious sound known as The Hum has been reported worldwide for decades, yet its source often remains impossible to find. Researchers tested whether people who hear it have exceptional low-frequency hearing or measurable sounds produced inside their ears, but neither explanation fit most participants. The strongest possibility is that many cases involve low-frequency tinnitus, even though the sound seems completely external.