Hi everybody!
I’m playing with a Raspberry pi both with Volumio and piCoreplayer.
As for the dacs I have an iQAudio Pi-da on the PI and a Bersford Bushmaster MKII external DAC.
I usually connect to the BM MKII in this way: from a USB port of my source, into a M2Tech HiFace2 Usb2Spdif converter, finally into the DAC via a coax cable.