Trying to do this:
Get no error messages but it does not work. Is there a conflict with “The Button” for Pisound. Like that the GPIO pins are configured in a specific way by default in PatchboxOS?
Thankful for help! Need to protect my SD card since power has to be disconnected multiple times in headless mode.
Why not simply hold the Pisound’s button for 5 seconds to trigger shutdown? 
Otherwise, what pins do you intend to use for this? Double check with General - Pisound Documentation whether the pins are not in use by Pisound.
Haha, I do not have the Pisound, I have a different setup.
Coolest thing would be if I could hook up my own button to act as The Button. Else maybe I should disable The Button?
patchbox/info shows:
pisound_btn_installed=1
pisound_btn_version=1.15
I was going to install the button on GPIO pins 39&40
Ok, pins 39 and 40 are not affected in anyway by pisound-btn or Patchbox OS, so it’s probably something else.
cool, but why is pin 40 red ( General - Pisound Documentation )
edit: now it works maybe because I did this
sudo usermod -a -G gpio <username>