Embbed Albumart not shown correctly

Hi,

My albumarts aren’t shown correctly. The problem is that each file shows the same albumart, although each file has its own different albumart embbed. Under the my music menu I disabled download albumart via internet and I enabled show embbed albumart.
I mounted the directories via nfs server and playback works fine. Only the cover issue disturbs. I also did a reset of the albumart and I tried to delete /data/albumart as told here: https://github.com/volumio/Volumio2/issues/445. Nothing worked for me.
The possibility to put a cover.jpg in each folder won’t work for me, because my directory structure is like this:

/directory/file1,file2,file3,file4…etc.

not /directory1/file1, /directory2/file2

Due to that it is not possible to work with a cover.jpg in this folder.

Can anyone help me out?

I am on Volumio2 System Version: 2.389

Edit: My id3 tag structure is as follows

File1
Title: xxx1
Artist: yyy
Albumartist: yyy
Album: zzz1

File2
Title: xxx2
Artist: yyy
Albumartist: yyy
Album: zzz2

Means that there is always the same artist but the album name and title is different.

same_cover_in_each_file.jpg
dir_structure_no_coverjpg_possible.png
embbed_albumart_on.jpg