Try talking to Mr. Roboto Automated Elite line when you're on a taxi and they're making an announcement over the PA system. Good luck! It keeps prompting you that it couldn't understand (same frustration I had with the automated flight status voice recognition software).

I told them when they tried this before that they need a hybrid voice/touch tone recognition system if they're so hell bent on going to this voice recog. Now for the most part it is hybrid, until you get to the enter your One Pass number prompt.