From DeFacto Sound, you're listening to 20,000 Hertz.

The stories behind the world's most recognizable and interesting sounds.

I'm Dallas Taylor.

This is the story behind the mysterious Windsor Hum.

There's this place right on the border of Detroit, Michigan and Windsor, Ontario, Canada,

where there's this hum.

It's so low, you can't really hear it at first, and you can't hear it everywhere.

But sometimes, in just the right place, the noise gets so loud that some people's dishes rattle.

And nobody knows what the sound is, or what's making it.

But it keeps people in the surrounding areas up at night.

It's known as the Windsor Hum.

Listen to it with me. This is an actual recording of the hum, but we've applied some processing to make it more audible. Imagine you had this sound

just there all the time. When you woke up in the morning, when you went to bed at night.

And the longer you heard it, the louder it got because at some point, when you weren't paying attention, you became attuned to it.

It became a part of you.

Would it drive you crazy?

I don't think I can handle it.

And this isn't the only place that this happens.

They've been reported around the world.

Everything from animals, machines, to people's own ears and even the Gulf Stream, all have been blamed for hums.

But their sources generally remain a mystery.

They can cause health problems like head pressure and nausea,

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