... and a hundred other repeated voice menu messages when using sat nav/b&me.

Does anyone know if they can be turned off?

Aside from being annoying, they slow down the whole process while I am trying to enter my destination while sat at the traffic light. As soon as I move, it loses all the data I have input to that point.

Can I disable these spoken instructions? And can I change the settings so that SatNav retains the information I have programmed in, so that I can complete it when I next stop?