Unfortunately there is no easy option here. Replacing the infotainment system with a new part from Volkswagen is very expensive, but comes with the assurance of it being brand-new and we would hope with some form of guarantee. Buying a used part is considerably cheaper, but there is no guarantee that the same fault could occur. Ultimately it comes down to how much you are prepared to spend on your car to keep it functioning, although you may wish to seek a second opinion from an independent Volkswagen specialist or car audio specialist who may be able to offer another solution.