I bought one of these devices last week for a garage system that has an older Harmon Kardon receiver with no digital or wireless capability. So same application. The little Fiio aboslutely breathed new life into the setup.
Last night I streamed A Dead and Company concert from Nugs.net. So I used a USB cable from my laptop (which was wifi streaming the concert) to the Fiio and Fiio RCA outs to the Harmon Kardon. I was just using the Sabre DAC in the Fiio. Worked flawlessly all night, and with respectable sound.
The Fiio is a darn swiss army knife. Does just about everything with D to A, BT (send or receive), USB, coaxial, Toslink. Worth the money.