I've had a problem several times in the past 12 months (and therefore with MC24 and MC25) where a large batch of tracks seems spontaneously to have been set to a single piece of cover art.
When this first happened I put it down to error on my part - I could not figure out how I had accidentally change the images on around 10,000 tracks (my library has 190,000+ tracks). I guessed I must have done something silly although I couldn't figure out any pattern which might suggest that I had inadvertently selected a batch (such as all works by a given artist/composer, or all works in a particular folder). The undo function wasn't available.
I've noticed this has happened a couple of times during the year, generally with much smaller batches of tracks (although certainly into the four figure range). Again, no obvious pattern, but on those instances, I did not notice the event until long after it had happened.
The same thing has just occurred, and I am reaching out for any suggestions. My observations:
a) 1,460 tracks were changed
b) the artwork installed was almost certainly on my clipboard - I had updated the correct album with that artwork last Friday. That was almost certainly the case in previous events.
c) I was nowhere near my computer when the updating started (based on the date modified)
d) as with last year's event, no undo option was available, and MC crashed when I tried to select any of the tracks
e) I can see no pattern or reason for those tracks to have been chosen, although it does seem to have affected all tracks in the albums impacted
If anyone has any insights into what might be going on here, Id be grateful. If you have any suggestions for how to restore the overwritten artwork, that would be wonderful.
If any further information would be useful, do let me know.