On the December 26, Fly to the Sky's Hwanhee explained the small mistake he made during his performance at the '2014 KBS Music Festival'. 

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During the broadcast of the '2014 KBS Music Festival', Fly to the Sky and veteran singer Lim Chang Jung held a collaboration stage in which they sang each other songs. 

During the performance of the song "Then Again," Hwanhee surprised viewers when he paused awkwardly during his part, possibly because he was struggling to reach a note. 

Although the moment was brief and the mistake was small, it seems that Hwanhee felt compelled to explain himself anyway, as he took to his Twitter and wrote the following: "It's been a while since I've done '(KBS) Music Festival'... yet in the end, because of my concert and other activities... although I want to be a singing machine, because I'm human I wasn't able [to perform my best]. I will soon be recharged again and will properly show you [a good performance]. To my family of fans, everyone, goodnight...." 

Hwanhee's performance mistake can be seen at the 2:06 mark in the video below: