Hi John
I've just driven to/back from Austria in my 2007 S3 and I have exactly the same issue as you describe. I simply kept trying it until it worked. To be honest, I'm not too fussed as I just put it down to another one of those "Morgan" features.
The one thing I will say for the Morgan mind is that it covered the whole 2000 mile journey there and back effortlessly. Mechanically it's a strong car. So my view is simply so long as it starts and moves when and where I want to go, I'm happy.......the bonus features I can live without.
I got pulled for speeding in Germany (43mph in a 30mph.....would you believe it having come off the unrestricted autobahn). Spent 10 minutes talking the inquisitive police officer about the car..let me off with a 35 euro fine....fairest police officer I've met.