Digitakt with Digitone in Ableton

Hi there,
I hope someone knows how to set up Digitakt w/ Digitone in Ableton.
What i did so far:
Updated all OS and Overbridge to their latest versions.
I added Digitakt to Ableton like explained in this YT video: https://www.youtube.com/watch?v=inKIWJ1Ck6I
That works like a charm.
I also connected the Digitone with Digitakt like described in Chapter 16.2 and this works also: When I plug in my headphones into the Digitone I hear the Digitakt in sync with Digitone.
But when adding Digitone to Ableton the tracks remain silent.
I can see it in Overbridge though. I also connected both (DT and DN) via USB (separate Hubs) to the PC (Win10).

Does someone know how I could fix this?