AUDIO GD R2R 2 .... USB not recognized

Hello There

I have 2 Pi2 unit, I use both for parellel listening in flaw way since some time so I’m pretty sure the unit are working.

I bought recently the new R2R and i started testing yesterday, everything is ok using windows or daphile, when using Raspy with Volumio system alt without particular other signs

I’m starting to think is an HW issue, anyhow I have changed USB cable, Unit, memory card just to skip surprises and I have also changed the way I power raspberry (Using a multiUSB unit and the Samsning note 3 USB charger)

I wrote Kingwa to understand is something may be changed with Amanero interface, I had in fact to re-install driver on window

No idea now about how to go on, a bit frustrated …Ideas ?