I have a 2005 A6 Avant, (new shape) with an MMI; colour screen; DVD sat nav; Bose sound; 6CD changer, etc. Can anyone tell me whether this is the same navigation system as the "RNS-E" system which seems to be included in the latest spec as "Navigation plus". Both systems are DVD based for navigation data, but are they compatible? Does anyone know? Can anyone help please?