To make sure I understand correctly, it literally says "Album Artist" under the album cover? Or does it say some artist's name?
I didn't quite understood but yeah my guess would be that some tracks on same albums are missing "Album Artist" tag. The ones that have album Artist tag are displayed as another album and the ones which are missing are displayed as another.
Hit File->Tools->Tagging Tools ->Other "Files to Edit" Filters->Show Albums With Inconsistent Tags
Slelect multiple files at once and recitify the tags accordingly.