Cubase 13 project clips locked bug

Well this is a weird one.

I have 3 instances of Omnisphere in this project. 2 are multitimbral, multi-out instances. These two were originally disabled in my template, then I enabled them to start work. ,The third is just one single instrument track, monotimbral. I was getting weird CPU spikes so I froze this track.

When I re-opened the project, the second multitimbral instance had become disconnected from its instance of Omni for some unknown reason. I reconnected all the tracks, and it now plays fine. But - all the clips in this instance are now locked with the padlock icon in place, and I cannot move, or even open them.

On the info line, however, it says these clips are NOT locked. I try to force them to lock and unlock from the Edit / Lock menu, and nothing changes.

So pretty sure this is now a corrupted project. I have a horrible feeling this is all to do with our old friend the enabling disabled tracks from a saved state, and it’s corrupted the session somewhere. Can anyone suggest a way to get my session back into working order? Thanks.

EDIT - I closed cubase, re-opened and the clips magically unlocked. Hurray, but it’s made me really nervous about disabled multi-out tracks again…