Rascal Flatts asked the same thing you're asking: What's a Hum-Off? But a few minutes in, the country trio were big fans of this new style of karaoke.

Gary LeVox, Joe Don Rooney and Jay DeMarcus hummed hits by the Temptations, Dolly Parton, Trace Adkins and ... hmmm, who is that one country group? Rooney was stumped by the final Hum-Off song. Can you get it before they do?

The concept is simple: Pick a song, try to hum it and get your bandmates to name that tune! The trio played during an interview prior to the 2017 ACM Awards in Las Vegas. We talked about serious things, too, like their new single "Yours If You Want It" and the upcoming Back to Us album, dropping May 19.

But back to the humming. You probably won't ever see this group singing "Honky Tonk Badonkadonk" on stage, but they can hum the heck out of it.

The Swon Brothers Did the Hum-Off Too! 

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