I’d noticed there was a problem but not that it always goes to track one.
I also noticed that even if you arm the correct track after using undo sometimes all you get us an empty box with no audio or with audio from the mike input when you do try to record.
If you eject the input App from AB and reload it Cubasis creates a new track and all is good again. That said I thought Cubasis was meant to know when you plugged an App in that you had already created a track from AB with and put it on the same track?