iTunes changing star ratings

I noticed this in Novmber of 2019, and at first I thought I had just accidentally changed some ratings manually but as time went on it was spreading. I knew it had to be in something that got changed on an upgrade which was doing it. It was wiping mostly 4 star and 5 star ratings to zero but it was also changing zeroes to 5 stars and changing 5 star to 3 star, 3 star to 2 star, and so on. When I learned about the gray star ratings, I set all album ratings to zero through iTunes and then saw that some of them had turned to blue star ratings which were also wrong. I reset my whole library to zero ratings and started manually putting the ratings back in, but over time I noticed they were being changed again. So I got Apple Support involved and we are still working on a sure solution, but this is what we have discovered so far:

1. When you export a playlist, create a new library file, and import that playlist, sometimes it wipes and and changes ratings.
2. Sometimes when I plug in my iPod, that will trigger a big ratings change in the library, even for stuff I had not played lately. However, that doesn't happen every time I plug it in.

So best guess is that when a library is opened, something is going in and deciding to change stuff around only if a certain daemon or process or whatever happens to be running at the time. That's not official, just my guess. I have phone call scheduled today for more troubleshooting to isolate this and I will post again when I have more info. But if you can take a look at this and see if any of it matches your experience, please let me know.

I am sure the problem is in the iTunes app or a process that's running in conjunction with the app in some manner. For my part, here are the facts that push me that way:

1. I am using iTunes 12.8.2.3 on High Sierra 10.13.6.
2. I do not use Apple Music or Apple Match; the reason I stopped using Apple Match was because it kept changing my metadata (typically year of release).
3. All my music is stored on iTunes in the form of purchased and imported-from-CD files, no ripped bootlegs or illegal downloads.
4. I only play music from an iPod classic (with rare exceptions) which I sync manually with iTunes via a wired connection.
5. I don't sync wirelessly even though those options exist for my iPhone and iPad.
6. All ratings are done only in iTunes itself, never on a play device.
7. I have a huge library (almost 35, 000 tracks) though some of that includes voice memos automatically transferred from the iPhone.
8. All albums have been manually set to automatic rating of zero.
9. All tracks were manually set to zero and ratings were being re-applied manually.

So since this started, I have been screenshotting each page in iTunes as I get the correct ratings reapplied and saving them to compare with the library as it stands while I rebuild it. This is how I am catching when it changes and which ones have changed, and to what. Most of the time it's taking 3/4/5 star tracks and setting them to zero, but not always. Sometimes it re-rates a track from 5 to 3 or 2 to 5 or 3 to 1 or whatever. So far there has been no discernible pattern but I keep saving data and hope to stumble onto something soon.

Unfortunately this is not fixed after all. About 10 days after I wiped all ratings and started restoring them by hand, I had only gotten part way through the A's when I noticed they were getting changed again. Take a look at these two screenshots. The first one was made on 12/7 the day I started cleanup. The second one was taken today. The red arrows show the three changes on this page (there are 5 more which are just more of the same). You can see that in each case it took a song I had manually rated at 3 or 4 stars and wiped it out to zero stars. iTunes should never, ever, ever override a manual track rating with its own value, much less wipe it out completely.

Thanks, that script helped BUT there were still some mysteries: first, the album ratings were not all grey, some were blue as if they had been manually assigned (they weren't). So after I ran the script on the grey ones, I had to go back individually on the blue star albums and manually assign no rating, at which point they changed to grey stars. I then had to run the script again to get them to disappear as well. However, neither of those restored the manual track ratings to their original value, so now I have to back through the 34,245 tracks one at a time and fix them as well. Thanks, Apple!

I don't use either Apple Music or iTune match, so I would have to know for sure when this change started. I only noticed it in the past couple of weeks. With 1,586 manually created playlists and 210 smart playlists, it will probably take me less time to just go through a line at a time and set them all back. But it's good to know what to do in the future if this should pop up again

I have been working with Apple Support on this since last year. We do not have a fix yet but the case is still open and investigation is ongoing. The grey star problem and the blue star problem are two separate issues. I am curious if you sync your device or devices with iTunes through a desktop or not (as I do). This is where it's easiest to see the problem and take steps to fix it.

When I first discovered the gray star problem, I found that some albums which had automatic rating had two layers: incorrect blue star ratings and incorrect gray star ratings, sometimes both. For example, I might find an album which had all tracks set to three blue stars that I knew should not be that way. When I cleared those manual ratings that I had not applied, I found that there were another set of gray star ratings under them that I then had to re-set to zero. So the gray and blue star problems are indeed related. The gray star ones are an easy fix; the blue star not so much yet.

I did find another circumstance that seems to trigger blue star wipeouts, but I'm still testing it to see if it replicates on repeated happenings. I will post that here when the time comes if it holds up.