How The Hum Works

There is a mysterious droning sound often described as like a diesel engine idling that is severely impacting the quality of life of 2 percent of people in places around the world. The thing is, no one knows what's causing it - or if it actually exists.

Learn more about your ad-choices at https://www.iheartpodcastnetwork.com

See omnystudio.com/listener for privacy information.