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.
さて 苦笑いが聞こえましたが ドリルの音がキーンとしすぎたようですね 抑揚に問題があったようです　  では別のクリップも見てみましょう