How about something like stopping in the middle of your songs while they are talking, and staring at them.
When they look up to see why you've stopped, simply say "If you'll be quiet during my songs, I promise I'll be quiet during yours."

Of course, I'm a full time professional entertainer with over 30 years of performing under my belt, so I'd probably humiliate the bastard before telling him to shut the fuck up or get out. Nicely.

Seamus