Taking your questions/comments in reverse:
Raspbian Jesse Lite. I followed the instructions in this post except that I didn’t disable the on-board audio devices as instructed in the section on “Configuring your HAT”.
For Raspian Jesse Lite, the username is “pi”, password is “raspberry”. If you installed a different OS, check for instructions on the site where you got it. Or google for it. The instruction post explains how to get a terminal window and shell so you can log into the Pi and edit the config file and do other things. I changed the password for example, and changed the hostname to “metalpi” since this Pi has a metal case.
The other sound output devices besides the hifiberry that you see in the screenshot (2 and 3 and 4) are there because of the “dtparam=audio=on” line in the /boot/config.txt file. Since you haven’t been able to shell in and edit your config file yet, the on-board audio device setting is probably turned off.
To be clear, these are not hifiberry options or devices: they are on-board and USB audio devices on the Pi itself. The screenshot shows the on-board analog audio out (headphones), on-board HDMI out, and an entry for every USB dac that you plug in. A dac should identify itself with some distinct name to the USB driver. That’s where the “Benchmark 1.0” in bold in the middle column comes from. It was retrieved by Roon from the audio subsystem on the Pi which got it from the USB handshake with the dac.
Once you get logged in, edit the config file and reboot. Make sure you plug your Oppo into a USB port before looking for it in Roon. You might have to plug it in before booting the Pi, I dunno. If the USB driver doesn’t see it, the OS can’t see it, then Roon won’t know that it’s there.
Thanks,
- Eric