Max2Play is based on Raspian. You could check on this. Unfortunately, we cannot support any USB-DAC. If it is an option, you could switch to the soundcards we offer in our shop. We can guarantee full support and easy installation for these DACs.
There is another thing you could try out if you dare to do it: Use SSH to log in as user „root“ (password „max2play“) and enter the command
If your soundcard works now, use this command
echo "snd-usb-audio" >> /etc/modules
to save this setup.
Maximilian from Max2Play