Using a stereo -mono splitter cable just plays left speaker

I am new to using djay2 on a ipad air2 and i’m trying to pre cue with a stereo to mono split cable.

The problem is that the sound just comes out on one speaker and on one of the headphones.

What am i doing wrong?

While I don’t have the app right in front of me, I remember a similar issue that was solved by going into settings in the app – and adjusting the audio output/source from there. Forgive me for not being able to tell you the exact terminology-- but the point it was a setting that needed to be adjusted that got me up and running. However, if you’ve done this already, hopefully someone else can give some insight. Good Luck/Best Wishes!

Thanx for your answer!
If you meen the split output enable switch, its of course enabled. =)

I can’t find any other setting in the app thats lets the music comes out to both speakers.