Posting screenshots to better show what my problem is.
The first one shows that in standard view, the correct cover art is used.
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.
In theater view (3rd image), when actually selecting the movie, the correct cover art is again displayed.
So the only time the wrong cover art is being displayed is on the theater view wall.