It's never happened to me, but if it did, I would probably just roll with it. Just hold your fram tight and continue with what you were saying... As long as you appear confident I think you could probably overcome this obstacle.
As i've recently been learning with my new approach to the game, you will be suprised by the witty and interesting responses you can come up with by saying the first thing that springs to mind, and not panicking

Ritz