I've been to over 100 shows in 20+ venues just in Knoxville, and this heckler debacle is nothing new. Knoxville has a bad habit of having selfish hecklers at many different shows. But the fact is, in my humble opinion, Knoxville isn't alone with hecklers at Chappelle stand-up shows, nor is it all the fault of Chappelle's audiences here and elsewhere.
First, Knoxville needs to hush during shows, but a lot of the audience feedback on ticketmaster.com, for example, is saying the same thing about hecklers taking control over Dave's shows in many other cities—not just Knoxville.
Second, Chappelle had many chances to carry on with his comedy routine but chose to stop and chat with the hecklers over and over again when he could have ignored them and went on with his act. When he went into his long bit about the TV show Cheaters, the Knoxville audience at the 10 p.m. show hushed then listed and laughed for the whole bit—I know because I was there in the fourth row.
Knoxville will stop and listen if the performer handles it right. Jerry Seinfeld told Knoxville hecklers early on that he'd have a Q&A at the end of the show but asked the crowd to be quiet, which they did. George Carlin at the Ryman in Nashville, 2006, quelled hecklers by saying: "Thank you," then moved straight into another bit.
Chappelle needs to take notes on how to control the crowd and not encourage hecklers. I think he can do it! As a speech communication grad, the first rule I learned was: KNOW YOUR AUDIENCE. Dave needs to understand that his own huge success creates excited crowds. If not, Dave may just be too giant of a star to handle live acts—a la the Beatles. Let's hope not.