Got the same problem using a double set driving from the Steuerwagen. But after I replaced it with a single set driving from the engine, everything was normal. So I think there is something with the trainset, even if I am aware of buggy LZB on that route. I will try again today driving a single set from the Stw.
More info:
It seems to be a combination of a difference between the Steuerwagen and the engine, plus a buggy LZB on that route. Driving from the Stw, I can reproduce this fault any time. Doing the same Munster-Bremen gives no faults.