Error Covert Art for .MP4 files

[JulienKer]

When I first play a MP4 file the covert Art is the correct one and it creates art.png in Users/***/Library/Caches/org.videolan.vlc/art/arturl/***/
For the second MP4 file it still displays the correct covert Art and it creates art.jpg in Users/***/Library/Caches/org.videolan.vlc/art/arturl/***/
However afterwards VLC only displays the first covert art (art.png), irrelevant of the MP4 file played. art.png and art.jpg are never altered by vlc after the second MP4 file played. When Manually deleting these files, the correct covert arts are displayed for the next two mp4 files.

So is there a way to fix this bug or make the deletion of art.png and art.jpg automatic?