Hum.

This is coolbert:

The Taos Hum. But hardly limited to Taos, New Mexico, United States.

Paranormal phenomenon with the military dimension?

"This mysterious sound drives some to insanity, suicide"

"Several investigations have looked into the Taos hum. One scientist believes he has the most likely culprit."

Article Philip Perry NOVEMBER 16, 2017.

"The New Mexico town of Taos is artsy and picturesque, bringing in tons of tourists each year for its pueblo, arts festival, and other trappings. The town has had several celebrity residents including Aldous Huxley, D.H. Lawrence, Julia Roberts, and Dennis Hopper. But there is a dark phenomenon underlying this eclectic desert oasis, a mysterious sound that only a handful can hear, and a small few are tormented by. It’s called the Taos Hum." [not however confined to Taos, New Mexico, USA]

See the You Tube video "The Hum". The tip from the Internet web site bigthink.com

See also this interactive map the worldwide distribution of the phenomenon. Allows you to determine if "The Hum" has been heard where you live.

"The Hum" suggested to be as a result of Low Frequency [LF] transmissions in the 3 KHZ to 30 KHZ range as used to communicate with American submarines. The submarines of other nations too I might well imagine.

coolbert.