[Solution found below -- user error]
I just did a "Run Auto Import Now" (I don't use otto, only run him when I need him)... on my audio directory. It says "Imported 23495 New files"... WHAT? I don't have 23495 new files! All the files with non-taggable formats have lost their tags (wav, midi, png for coverart, documents for the albums etc etc). That's hours and hours of work gone
All these files were already in the library (bar an album or two - the reason for me running the auto-import)
-I have not moved the files or renamed the files outside of MC.
-I have not changed the drive letter.
Why is MC picking them up as "New Files"?
Fortunately, I have a library backup from right before I did it. So I restored the library.
Here's what I found:
All the "New Files" are happily in the MC library and are playable inside MC
I ran a "Update files from library" to make sure they're def not disconnected
Running the auto-import again with "Ignore File Changes" produced the same results.
So here's where I stand. I have a working database with all the fields filled out to my liking, but I can't run an import anymore without MC thinking that the files are "New" and wiping the tags accordingly. Taggable files are also recognised as "New", but at least all that info is stored safely in the files.
I have definitely run auto-import in the last few weeks and it's been fine... so I have no idea what's happened.
What can I do?
(PS this was first noticed by me with 409... have since installed 413 and 414 with the same results)