I didn’t had too much time do see it, but by my point off view your connecttions has some errors, that I will try to explain.
First o all, let see this 3 sites:
DAC page: https://www.audiophonics.fr/en/diy-dac/audiophonics-i-sabre-amp-dac-es9023-class-d-amplifier-2x30w-tpa3118-p-11800.html
Power Management Board: https://www.audiophonics.fr/en/diy-kits-boards/audiophonics-pi-spc-power-management-module-for-raspberry-pi-p-11125.html
Tutorial for Power Mangement on Volumio: http://forum.audiophonics.fr/viewtopic.php?f=4&t=1578
And so, we can see that the conections to power board that you made does not match with that especified in this figure in DAC Page:
I sugest that you change your connections to match exactly as above anda try to see the Forum that explain how to insert the correct Volumio Script.
And atention that you must connect power to your system directly to DAC board that will send power to Raspberry Pi.
A hope that it help you to solve the problems.