Remote Bluetooth shutter not responding when HDMI adapter is plugged in

Hi. i've been auditioning different camera apps all year, and with each one i've tried, my remote Bluetooth camera shutter button stops responding as soon as i have my HDMI adapter plugged into the lightning port (and am beaming the image out to a monitor). It's not the button; i have tried four different buttons, and they all stop functioning.

i really need to be able to see my work on a monitor, because the phone's screen is too small for me to catch focus issues, or stray hairs or lint on the items i'm shooting.

i've noticed that the shutter button + adapter combo works fine when i use the iPhone's native Camera app, but that app lacks features that are important to me, like manual white balance.

Has Apple locked its developers out of this functionality (Bluetooth + HDMI out), or is it a simple bug fix that i can reasonably request camera app developers make?

Thanks!

• Ryan