Hi there,
As far as I can tell, REAPER prevents MIDI feedback routing even with the “enable feedback routing” preference checked. No big deal, as I’ve learned that’s standard practice across DAWs.
But it seems that REAPER either “plays it safe” or is simply incorrectly detecting when MIDI feedback is being attempted. I made a separate post about it
here.
The issue seems to be that when you send MIDI to the receiving track, then send audio back to the send track, REAPER appears to think MIDI feedback is being attempted, and thus it kills the MIDI send to the receiving track. This doesn’t make sense because MIDI is not being sent back to the send track! Only audio is being sent back. So there is no MIDI feedback path (though there is potentially audio feedback if the send track sends audio + MIDI, which REAPER allows).
Additionally, if the send envelope is muted, the same situation occurs… even though the send is muted at that point in time! Please refer to my original post linked above for a more in-depth explanation.