Khadas Tone Board - No sound with Pi 2B?

I have been using Volumio with my Pi 2B for a long time, it’s been working great using USB out from the Pi to the USB in on my Parasound P5 preamp.

Today I installed a Khadas Tone Board on the USB out from my Pi 2B, and I’m running the RCA out from the Tone Board to a line input on my P5 preamp.

The Tone Board is recognized as “Khadas Tone Control” by Volumio and defaults to hardware volume control. I start a track, Volumio appears to be playing it, but I get no sound from my stereo.

I’m using the USB cable from Khadas, although I did try another one, still no sound.

I’ve tried ‘factory reset’ on Volumio and I’ve updated the firmware on the Tone Board to the newest one in the folder on the Khadas site, still no sound.

I’ve tried every possible combination of settings I can think of in Volumio’s Playback Options, still no sound.

Is there something I need to do that I’ve overlooked? Do I need to manually install drivers on my Pi?

Is the Tone Board not compatible with the Pi 2B maybe? Do I need a 3B or 3B+? I’ve noticed all three entries on the]DAC Compatibility List are using a Pi 3B or 3B+, perhaps the 2B doesn’t put out enough voltage on the USB port?

My uh, RCA plugs weren’t fully seated in my preamp.

I’ll be over in the corner dying of embarrassment if anyone needs me. :neutral_face:

edit: wow, this DAC is insanely good