Tracks in folder do not all solo or mute as they should

For example I have a folder, DRUMS, and there are tracks with the different drums in it. I should be able to solo or mute all by pressing the button on the folder, but instead have to solo each individually, as though they aren’t in a folder. Strangely, when they are then all individually made to all show solo, pressing the mute on the folder track mutes them all. But pressing solo again leaves them all muted.

I had a couple of similar issues, including the folder track showing deleted tracks on the track display. All I did was to move everything out of the folder, delete said folder and then create a blank folder and repopulate it manually.

I’m finding, even as I just moved to Cubase 13, that creating the new folder and moving into it made no difference.