Man, this may sound drastic, and I hate to sound so anal, but I would call the chief on this. Simply because you would be held just as responsable for any violation (or worse) which may come from this guy yapping at the wrong time.
On a side note, I am not sure who you fly for. I am just an FO-in-training and have yet to go to sim. But my company spent several hours in indoc hammering this very situation into our heads. I could be completely over reacting here. Just my 2 cents.