Oh, Akdong Musician.  You can't forget that they're siblings after all!

On the May 16 airing of KBS coolFM's 'Park Ji Yoon's Music Plaza' featured the family duo with Park Ji Yoon saying that they really did seem like 'display window siblings' and asked what they were saying to each other after their live performance on the radio show. 

Suhyun relayed, "Right now, while singing live, oppa hit the wrong note," and Chanhyuk denied this with, "No, I didn't.  To tell the truth, that's a singing method I've been practicing lately," causing laughter with his excuse.

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Suhyun did not give up, saying, "No, that's not it.  You hit the wrong note. He had to go past that as a professional, but then he looked at me.  He was trying to get past it with laughter, but he should have just [sung] right away.  He should've been like a professional."

At her lecture, he said as if intimidated, "I'm sorry," causing more laughter.