The +3V3 trick worked for me on GPIO 17 and RPi4, but anyway, to change the pin and save it between reboots, you have to override the pisound-btn.service file. See this topic where I explain how to do it for modep-mod-ui.service, and do the same for pisound-btn.service, edit the command line appropriately in your copy of the pisound-btn.service.
You can find out the current path of pisound-btn.service using this command:
sudo systemctl status pisound-btn