Hi Ralph,
Thanks for replying. There is an option to enable autostart. This works, but does not seem to run bootloader as root. That is really the heart of my issue.

Bit more information - I think my problem one that at least one other person has had. If I disable autostart and run Bootloader as root - GPIO works (as they say it does). The issue is more that if I enable autostart when setting up AirPlayer, Bootloader is run as a user program and not root and ...

Just wondering if anyone has worked through a similar issue. I've got AirPlayer ARM running on a RPi 4. As I understand it, as the video is via HDMI, I should be able to utilize the GPIO of the Pi to connect to a rotary encoder. I put a current version of the raspberry pi linux distribution on the ...