Loop Playback - Problem setting loop in part.

Hi all.
I have a score that has multiple parts, and I am on the tab that shows just the clarinet part.
When I select a note and click on the "Set loop in position" button in the Play panel, the blue flag does not move to the note I selected (which happened to be a rest when I first tried it). It moves to the start of some bar.
The same problem occurs with the "Set loop out position" button.

When I am on the tab that shows all the parts, it works fine. I can set the start and end of the loop, then go back to the clarinet part, where the flags are correctly set.

The version details are:
OS: Windows 10 (10.0), Arch.: x86_64, MuseScore version (64-bit): 3.6.2.548021803, revision: 3224f34

Thanks
Don.