Yes, I've seen it happen sometimes

It's one of those strange things that happens to other people but never to me :-)

I believe it is a data message clash on the databus but I have never found the root cause of the issue

Some cars seem more susceptable to this problem than others

So at this stage i can only suggest doing what you do - and also being conscious not to overload the data bus by doing too many things at the same time.

I always, for example, make sure that the radio is turned off and that the ign key is in Pos1 (not Pos2) when programming anything with NavCoder. Turning off the radio reduces the data traffic immemensly, turning off the ign to only Pos1 reduces it even more.

Regards, Jochen (NavCoder author)