Hello,
I’ve discovered Volumio a couple of weeks ago and I really like the project!
It looks stylish, and it worked out of the box with my Raspberry Pi 2 and the Marantz HD-DAC1
connected to the APPJ PA0901A mini Tube-Amplifier and two Klipsch RB-51 II Compact-Speakers !
Not loud, but fine! 
Thank you for the great work!
Grullemuck