Akdong Musician made an appearance at SBS's 'Cultwo Show' radio program on June 6.

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On this day, the siblings performed together and then the DJs said, "Akdong Musician's songs are good, but they're hard to sing along to."  Suhyun said, "There's no break, so singing live is really hard," and expressed her resentment towards her brother.

Chanhyuk replied, "That is why our throats haven't been good; we've been doing a lot of lives.  Suhyun says it's hard to sing and resents me."

You could never tell they're struggling though!  They always sound so good, right?