Hallo,
If I just remove the SUB group bus, Ardour doesn’t crash yet.
The SUB group bus has been removed. But!!! If I now call up the context menu of the mono group, the “Remove SUB group bus” button is still available in the context menu, although the SUB group bus has long since been deleted. Now when I click the “Remove SUB Group Bus” button, Ardour 7.0 crashes.
The SUB group bus is otherwise a great idea, which I will use more often in practice. That makes my work easier. You’re still fixing the crash.

