Reply on this forum then people can learn from the experience. I reckon you should be able to get rid if it. The first one I got rid of first time with the method documented. The second one was more stubborn but I had, had the firmware changed by then so I had been entering the incorrect clear code since I hadn't recomputed it - it changed after the firmware change. Then I subsequently read on an Ozzie VW board that you in some instances have to 're enter it several times since they get stacked up. Having done that, they cleared.
So getting the clear code computed correctly and bashing it thru several times did the trick, least on the Seat Plus unit. I'll work it out for you using the Audi method.