In the middle of playing my very first round with one of my adult children, the other adult child audio recorded part of our game and started replaying their recording to disrupt the rest of our game. All in good fun and we laughed pretty hard. Also, we had fun with the game.

That's excellent!

I don't think that could be prevented, either. You could have the protocol exchange signing keys at the start and sign every message, but it's stretching the amount you can do with available audio bandwidth already so I expect that either wouldn't work or would become unbearably slow.