Drivers may accidentally enable this Accessibility option on their tablets. This will cause the tablet to read out everything on screen and will require them to double tap to make any selections on the screen. 

You should be able to disable it by going to "Accessibility" -> "Screen Reader" -> Toggle "Voice Assistant" off

If by chance, you are unable to turn it off that way. You can reset Accessibility settings by going to "General Management" -> "Reset" -> "Reset Accessibility Settings" -> "Reset Settings" -> "Reset"