I’ve done a lot of gigs, I’ve played for all sorts of people. Best thing I learned was to stop playing places where hecklers tend to be. Other than that, I mostly ignored them. One time in a small bar about 15 years ago, I stopped a song dead, asked the drunk heckler and his two friends 5 feet away if they had a problem. They said “No, man.” So I went into the next song. Hecklers are haunted by the shadow of their voice, convicted by what they are and are not.