I am having an issue in which my Schiit Modi no longer seems to be recognized by Volumio. It used to work just fine. Then, it started to requiring me to reset the device more and more frequently to get it to work and now it does not seem to work at all. I can plug it into my Windows PC and the OS sees the device just fine. I was wonder if anyone could shed some light on this issue.
I am on the latest stable version of Volumio.
Hi,
Try it again with a powered USB HUB between DAC and PI.
The Pi 3 gives plenty of power for a Schiit Modi. I have tested this extensively using a USB power monitor.
Don’t believe it when people say you need a power supply. That seems to be the default dumb suggestion when it isn’t working. 
You may be having the problem described here:
problem-with-shiit-dac-modi-usb-port2-cannot-enable-t3264.html
In my case I had to add "dwc_otg.speed=1“ to /boot/cmdline.txt to get it working. Now it works but with occasional dropouts which I guess is form the slow USB speed. This whole experience has been much more painful than I expected…