Most album covers (cover.jpg) not shown

[Roelofpieter]

Hello. I have installed Elementary several times on multiple machines, but I run into the following problem every time. Most covers are not shown after indexing the music. Music is stored in (local) ~/Music/Artist/Album directory structure. Directories contain a cover.jpg file. Most files are about 500x500 pixels and smaller than 100kB. I see no pattern in what covers are show or not. Other players (Melody, Lollypop) do show all covers (screenshot added, comparing Melody (left) with Music (right)):

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