If you are talking about music files that you D/Led from other users than the album art has been included at some time by a fellow user... It is not something that you could block or 'prevent' as it has been included in the tagging info.

I make a point of doing my best to acquire and include album art in the tags of any files I share, but you surprise me if you are suggesting it is a 'problem' as the vast majority of files being shared do NOT include album art.

Curious where you are seeing the album art... Musicmatch Jukebox ?

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