Prelisten doesn't work with line6 sonicport

I have a line6 sonicport that I connect to my IPAD lightning port.…

In the earphone jack of the ipad I connect normal headphones.

However the precueing doesn’t work. See screeenshots:

I get either only earphones to chose from or only sony vx.
What I want is of course to chose earphones for precueing and sony vx for main output.

* I tried restarting djay app and doing things in many different ways
* I DON’T want to buy the griffin cable and DJ in mono.