I have tried to reproduce this with the extra debugging, but have so far
not been able to (which also explains the delay in replying).
There was one reply suggesting that the close could be triggered by
the "user pushes tray in manually" sensor (which I had not thought of
myself). I normally never do that, but when I fiddled with the tray it
did close very quickly once. After that I did push it in a few times
(with some force needed as you'd expect) and the problem has not
reoccurred since.
So I'm currently inclined to blame that sensor as the cause of the
problem, but will keep an open mind and try further tracing in case the
problem reoccurs.
My thanks to all who responded and helped eliminate a number of possible
causes.
Cheers,
FJP
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