Okay, I hear you were laughing nervously because you too could hear that the drill was a little bit sharp, the intonation was a little questionable.  Let's watch just another clip.
저는 여러분들이 긴장하면서 웃는 것을 들었는데 드릴 소리가 좀 날카로웠고 음조는 약간 의아했을거에요.  다른 영상을 볼까요.