Just ripped a disc, and PotPlayer/MPC-HC plays it in kind of a 1:1 aspect ratio, it looks square. VLC plays it fine.
I don't know what to troubleshoot, so here's mediainfo: https://hastebin.com/raw/javunefaxu
Please post here for issues related to Blu-ray discs
2 posts • Page 1 of 1
According to the MediaInfo, the size of the video is exactly 1920x1080 so it doesn't look like there's anything wrong with the file itself. I would just ditch this other player if I were you and keep using VLC. Alternatively, get Plex and use their player - it also seems to be able to play anything you throw at it.