Posting screenshots to better show what my problem is.
The first one shows that in standard view, the correct cover art is used.
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However when I go to theater view an incorrect cover is used (2nd image). It is using the cover from a tv series I have with the same name.
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In theater view (3rd image), when actually selecting the movie, the correct cover art is again displayed.
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So the only time the wrong cover art is being displayed is on the theater view wall.