LOL, I have encountered this very problem at my gym. I've been going to spin classes for several months now and I have two instructors who frequently sing during class. Regardless of whether they have good voices or not, no spin instructor should ever sing in class in my opinion. If I wanted to hear karaoke, I would go to a karaoke bar. I go to spin class to work out. I've actually stopped going to the two instructors classes who sing because it annoys me so much.
