I have had a few series in mkv format that all episode info was correct. I then tried to add a few episodes and they were wrong. I cleared the show to try to repair data. when rechecked all episode data the same. posters and episode numbers are correct but episode descriptions are all the same and incorrect.
Ones I've noticed it on were Portlandia and The IT Crowd
It seems to be picking episode titles from "Season 0" instead of what it should be picking since some of them are showing up as "Promo" titles and on some shows those seem to be categorized under "Season 0"