Folks,
actually, my setup looks like this:
Digitone -> Digitakt -> Syntakt
The main output of the Syntakt goes through a compressor into the mixer.
This works well. But now I analyzed the spectrum in Live and saw some peaks in the frequencies.
So I set the main output volume of the Digitakt and the Digitone to the highest level and at the same time reduced the external input volume in the Digitakt and Syntakt to around 30. Now the peaks have disappeared, but there is more noise overall.
Long story short, here’s my question 
What is the best combination of output volume and input volume to connect these little boxes?