Useful info from professional peeps

Read: Tricks of the Trade

witz.org particularly liked this one from a musician:If you have a rowdy audience that is keeping you from playing by chanting something (like a song name you’re not ready to do) have the drummer start beating in synch with the chant. Do this for a few moments and then slowly start speeding up the beat. The crowd will inevitably follow the beat and try and keep up with it.

In a short time the drummer will be drumming faster than the crowd can chant, and they will eventually collapse. Now launch into something with a good beat and a strong start — if you do it right, they’ll now be on your side and into the next song..