Thank you kpsiegel, normally i'm also not for downgrading.
I am going to get some information on the Waldorf site.
By the way, i also send an email to Waldorf with this problem.
I received an brief answer that i have to refer to the Pro Tools manual, because the device works properly under Ableton. Not the answer i expected to, but understandable.
But it didn't quite help me.
So i've read the whole manual, but nothing specific for my problem.
I also posted this issue on the Pro Tools forum, but 2 reactions which didn't help me.
It must be a Pro Tools matter, or better, my lack of experience with Pro Tools, because through midi and in Ableton with USB, it does work.
Best regards, JohnB