That Unique Sound Is Revealed [Video]

Last week I shared some audio of a very strange and unique sound and I asked you to try and figure out what is was. Now it's time to reveal the answer.

Let me first say that nobody correctly guessed what made the sound. In fact, no one was even close - but that is what I expected. I never would have guessed either. The whole reason I posted the video in the first place is because I was so surprised and confused by what I heard.

So watch the video below and you'll see what common item was responsible for that unique sound.