I use RPi2 with Hifiberry DIGI.
When I set the Volume Control Option to software the volumio 2.185 is hang up.
Volumio 1.55 or 2.114 work well.
Version 2.203 work well.
hifiberry-digi-pro-and-allo-digione-volumio-special-version-t6849.html
Thank you.