Logic Pro X Logic randomly changing MIDI IN/OUT configuration mid-session


Hi Group.

Strange problem here with my Logic X set-up. For some reason, Logic senses and changes the number of MIDI ins and outs available on my system at random unpredictable times - sometimes mid-song messing up what I'm working on.

I have the UNITOR-8 drivers and am using 4 UNITOR-8's as well as an NI interface in the AGGREGATE mode for MIDI / Audio. The NI and an Apogee Ensemble Thunderbolt are the audio interfaces.

Seems like something is happening on the MIDI bus that Logic is auto-sensing. Have used this setup for many years and have upgraded along the way - problem has been with me for some time but not sure when exactly it started.

Any ideas how to fix?


jr (LOGIC X 10.4.4, Mac MINI i7, Mac OS 10.12.6 soon to be upgraded to 10.13)
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Any chance you have Bluetooth MIDI enabled on some iOS device that comes near? I have had my iPhone decide it wanted to "play" and change things up a bit. My MIDI environment is much simpler than yours.