The problem might be the end destination.
And Oliver was right, of course.
I called the Kassel SEN line twice, both times they had to ask a supervisor and unfortunately I was not allowed to change my award routing from LAX - MUC to LAX - FRA.

So I enjoyed the friendly muc crew.
And earned 10k miles for an only partially working IFE.
They rebooted the system 3 times, but the movies wouldn't play,
only the music worked.