Develop Module - Before and After view comparison, Before has a corrupted white balance

Mac Mini 2023 M2 chip 16GB memory

Lightroom Classic 12.5 release Build [202308091523-68a7abd6]

1. When I press \ or YY button to view the before and after changes in the develop module it shows the before with a colder white balance. This starts partway through editing my imports and even if I have not made any changes the before and after should be the same. Looking at the photo in the library you wouldn’t know that there was a problem, the photo is as expected.
2. I edit my photos in the order they are in the folder.  The initial edited photos have the correct before, then the problem occurs and the remaining edited/unedited photos with the WB problem.  E.g. a folder of 114 images, numbers 84 to 114 affected.
3. Also, if I edit a photo and then press \ and find that the white balance has changed and become cooler, if I then return to the after view, very occasionally, I have lost all of my edits, they have reset to 0. The history is still there so if I click on each change the settings are restored back. 
4. Flickering.  Moving from one photo to another, not necessarily the next photo in the folder, when I press \ to get the beforeview, the screen flickers very quickly showing the last photo I used before on, then it shows the current one.  This can happen anywhere in the folder not just the ‘corrupted’ before ones.
5. Re-importing the photos doen't necessarily recreate the problem.