So, you have verified with the intended device that the files ARE there, and that they DO WORK-

just not with the apps you would like to use them with-

correct?

 

First, I would try a different music player.

There are so many out there.

Yes, it is inconvenient- at least at first.

But there is always the possibility to discover something that you like better.

At the very least, you can just try it to see what happens.

I use BlackPlayer, and I use an old version to avoid ads placed into newer versions.

https://blackplayer-music-player.en.uptodown.com/android/download/345945

Another one to try would be VLC.
This may be the best choice, as it will play all sorts of media, not just music.

https://f-droid.org/en/packages/org.videolan.vlc/

 

As for your images, we are not only talking album covers, I presume?

Like your personal pictures and videos?

For that I would suggest Simple Gallery Pro.

https://f-droid.org/en/packages/com.simplemobiletools.gallery.pro/

Yes, I realize that asking a stranger to download apps is odd.

These are all (except VLC) apps that I use every day, on all of my devices.

The point here is to see if apps that I am familiar with work with what you have going on.

If so, then we know that the problem is with your old apps, and not the card or the media on it.

Also, I am picky about my apps, so I do think that they are generally superior, lol.

Seriously, my devices are crap- but due to the apps that I use, I can safely say that I do more with my devices than the vast majority do with 10x the device.

 

Any luck?

 

I figured that you would lose that information.

To be honest, I gave up on playlists and favorites long ago.

Just too much trouble, and then they get deleted somehow or other.

It's just not worth the effort.
Shuffle play is my answer, and I can skip anything that I don't want to hear at the moment.

Did you try any of those apps, by chance?

There are some excellent things there.