Long story short, I was able to:
- Get a Pi 3 B+ running.
- Get it to recognize my Audiobox A96 (was plug and play).
- Get Jack running through the Audiobox (but only from the command-line) with jack -d alsa -d A96 -r 48000 -p 128 -n 3. Qjackctl will not run due to a bug in QT or something.
- Get Ardour running, start a new session and add a couple of Audio tracks.
- Map the inputs from the 2-port Audiobox to the 2 tracks in the session. I can see meter activity in the two tracks.
- Hear output through my speakers, but…
- Load gxAmplifier-x into the 2nd track to color the guitar sound. DSP ranges from 20% to 40% depending on the settings when starting Jack. Closer to 40% with the settings above.
The problem is the guitar sound I hear in the speakers is plain, uncolored. As if the master output from Ardour is not going to the Audiobox, though the “master out” green dots seem to be linked to the right hardware output. When I try to adjust output connections (through Ardour, remember qjackctl doesn’t work), either Ardour or Jack (or both) freezes on me. I have to keep killing processes just to try again. And yes, I have the mix knob on the Audiobox set correctly.
Should I start Jack with a different command or something? Why can’t I hear the effect of the amplifier sim on my signal? And why are Jack/Ardour so prone to freezing or crashing (which I experience on my laptop several times per day)?