UPDATE: Boss2 received and installed with no problems. Was indeed Plug and Play as a Roon bridge and is functioning correctly. However, there are a few disappointing points:
1. Sound = very flat and non dynamic (as compared to a Squeezebox Classic on same exact system/parameters). Bass and lower-mids are perhaps too rounded and full while HF are VERY restrained. No bite or controlled sparkle on top. It works but sounds dull and disappointing.
2. Aluminum case feet are uneven and the unit is unstable on a flat surface. Not a major problem but the unit is so light along with unstable slippery feet it becomes a bit unwieldy once your RCA and ethernet cables are connected.
3. There are no instructions or indications on the functionality of the 4 filters which are accessible by remote control or by joystick. These filters can be disabled or enabled but there is no explanation on what they do.
Finally, I had to install an SSH client to immediately update the DietPi software and this was successful with no change in sound or functionality.
So quite frankly, what I thought was an inexpensive option for a qualitative Roon endpoint turns out to be clearly inferior to a lowly +10 year old Squeezebox in terms of sound and functionality. Yes, it does function as a wired streamer/DAC but there are no miracles, this is a very modest and very basic product with average or below-average SQ at best (IMHO, to my ears and on my system. YMMV of course).
Brgds.