I have an iCON iKeyboard 4X, a cheap USB soundcard from adafruit, and I etched your iso. I also plugged in a USB drive with the following instrument downloaded:
Mellotron MK II Flute
It is in the root of the USB drive as follows:
On the first run, I checked systemctl status samplerbox, and it was not running, reporting an issue with smbus and i2c. I opened up your samplerbox.py, and changed the following top variables:
USE_SERIALPORT_MIDI = False
USE_I2C_7SEGMENTDISPLAY = False
USE_BUTTONS = False
This fixed the smbus / i2c error. On reboot, the system daemon is running fine, but no sound. I stopped it, and executed samplerbox.sh directly, and observed the following output:
Opened audio device #2
Opened MIDI: iCON iKeyboard 4X V1.06 24:0
Opened MIDI: iCON iKeyboard 4X V1.06 24:1
Preset loading: 0 (0 Flute)
Error in definition file, skipping line 1.
Preset loaded: 0
Any ideas what's going on? I did not make any changes to the definition file of the instrument. Also, I know that the actual keys are on channel 1 (not 0) of my keyboard (it strangely runs 2 different midi devices). I have tested the keyboard in other applications and channel 1 works.
I am very excited by this project. Hope I can get it running soon! Great work on the 8 second boot time and realtime linux. I have been trying this kind of stuff with fluidsynth for months and constantly running into problems, with crazy long boot times and audio issues.