MMI won't respond to buttons
 

The MMI joystick and buttons can easily get coffee spilt on them due to the location of the cupholders.

If the MMI is not responding to button presses, press all the buttons on the MMI one at a time to ensure there is not one stuck. If a button is pressed for a period of time, it will stop any additional presses from registering in the software.

If it still won't respond use the TEL + Centre Joystick Button + Top Right Selection Button to reboot the MMI.

Later cars was SETUP + Centre Joystick Button + Top Right button to reboot the MMI.