OP-1 midi controlling iPad no sound output through speakers

Hello fellow OP-1 enthusiasts, I would like your help on an issue I’ve run into while trying to use my OP-1 as a midi controller for iPad apps.

I’m able to control certain apps such as Audiokit Synth One over midi, I can see the notes being played but I’m not getting any sound from the app through the iPad speakers, nor through the OP-1 speaker or the OP-1’s headphone jack.
When I connect headphones to the iPad, I do get sound.

OP-1 is connected to Ipad via apple CCK USB connection, OP-1 set to CTRL

When I route the audio from the synth app to a recording app I can record it, so ther definitely is audio being generated. However to play the recording back I can only hear it through the speakers when I disconnect the OP-1.

I suspect the iPad may be seeing the OP-1 as an output device and therefore muting. This is reinforced by the fact that I can briefly hear audio for a few seconds after connecting then OP-1.
When I select the audio device from the switcher in control center, there’s no option to choose the internal speakers.

Anyone have any ideas ?