Radio/Sat-nav code problem .. any ideas ?

[Pinballer]

Hi to the RS6 group. I'm a Long term lurker, first time poster ...

Had my first RS6 from new (was company car !) sold it at 45k, now on my 2nd which is currently showing just 18k and sweet as a nut, and no DRC issues or any other problems so far .... except :-

The car 'forgot' its radio code for no apparent reason about 4 months ago, and I had to physically turn up at local dealership to get prove ownership etc, to get the code, all done free of charge.

Now 3 months later, codes gone again. But this time the correct code will not work ... I called the dealer and got the usual teeth sucking sounds and 'you need a whole new unit, cost is well over £1k ...'

Really ? Surely theres a simpler solution !

Anyone got any ideas on how to solve this ??