SOLVED: it work out-of-the-box using:
amidi -p hw:1,0,0 -d -r /tmp/bkup1.syx
but
It’s mandatory to check if:
- Global -> System -> usb config is set to “USB-MIDI ONLY”
- Global -> Midi Config -> Port config -> Output To is set to “MIDI+USB” (or “USB” only)
Thanks to all