Common fault, have you spoken to the dealer about it for a warranty claim? Even if not under warranty ask them to speak to MB UK for goodwill gesture / contribution.
mine went on the second day of ownership
they ran round like lunatics apologizing and fixed it with a new circuitboard
it was never going to be anything less than under warranty
Not the point, it is a known fault and you would expect it to last alot longer anyway. Get the dealer to push MB UK to fix it for free as a goodwill gesture or at least contribute towards the cost.
We had the same with the TT recently, cars out of manufacturers warranty, dealer got Audi UK to pay the full cost to repair as a goodwill gesture.