When “Prefer local metadata” is enabled and “Album Art” is "Local Files Only, Plex should look for album art in this order:
- Discrete file (a .jpg, .png, etc., file alongside the music track files. If the album has multiple discs in ‘disc1’ ‘disc2’ subfolders, the image file must be in ‘disc1.’)
- Embedded cover image.
It’s done in that order because discrete files are likely to be of higher resolution.
Question: What are your media file types (mp3, flac, etc.)? It may not make a difference, but it may provide a clue.
Things I know of that may prevent Plex from using (correct) embedded art:
- Corrupt image - obviously. Probably not the issue here.
- Embedded image is not marked as ‘front cover’ type.
- First track doesn’t have the embedded image - I suspect that Plex will look at track 2 for art if track 1 doesn’t have it, but I don’t know for sure. I do know that, if each file has a different cover (not supported – Plex does not support individual images for each track), Plex will apply the art from track 1 to the album and ignore the rest.
- Multiple embedded images - Several years ago, I noticed that, if there were embedded images for cover art and artist, for example, Plex would take the wrong image as cover art. I eventually switched to using discrete image files, so I have no idea if this was ever fixed (I suspect it wasn’t).
- There’s a discrete file that you don’t know about - Some apps, like Windows Media Player, would automatically download a cover art image into the folder with the music.
