I know this has been mentioned b4 - but my problem is slightly different, and it’s only started to happen since the update!
I’ve got several box sets of singles by Depeche Mode - and I can’t seem to get the album art to stick. On some you can only get “original” (relatively poor) pictures to “stick” - when you try to change the cover from any of the options - Google/Bing/discogs/photo album - it initially appears fine - then disappears. And on a couple there’s no pictures at all.
Any suggestions would be most welcome - I thought I’d just got the hang of it all - and it was all looking very nice and neat - not that suffer from any kind of OCD or anything 
cheers chaps (and any ladies also present!)