Similar issue with UNDO.
In Midi track, I create a new midi track, I configure Input and Output. I click on Undo, then Redo : The input and Output are reseted.
Worse !!
I record several Midi parts. I click on UNDO, then REDO… All the midi parts have been reseted, they are all empty …
Still the issue.
I set first input then output for midi track.
I click on UNDO, output is reseted. I click on REDO, output is still empty instead of back with the previous selection.