Megtaláltam a Kodi wikijében:

In some cases video playback is fine, but incorrectly sized so that it only takes up a small portion of the screen. This again is most likely a firmware issue, but a temp workaround would be to go into Android's system settings (not Kodi's settings) and change the GUI resolution to 720. Video will still render at 1080, and only the GUI is limited to 720.

Működött is egyből!

Üdv