I received some feedback from Arturia and this appears to be a known issue with ProTools. I've been given the following work-around which works fine:
This should normally work fine as long as you adjust a small setting in the Pro Tools preferences :
- Pro Tools -> Preferences -> Midi : Make sure to select "None" in the "Default Thru instrument" section.
- Once done, make sure to create two tracks :
Track 1:
- Put the MIDI In on your audio interface as you cannot select "None".
- Then the MIDI Out on the MatrixBrute
=> This track sends MIDI to the Matrix but does not receive it.
Track 2:
- Put the MIDI In on the MatrixBrute.
- Then the MIDI Out on the audio interface also, but you can certainly put "None" instead.
=> This track therefore receives MIDI from the Matrix but does not send it.
=> That way you'll be sure there's no MIDI loop <=
- Finally, make sure to define two distinct Midi channels for the Input and Output Channels through the Midi Control Center : See attachment