Vanilla Kodi on Dune uses software playback so doesn't fully utilise the Realtek video chipset. This means lower performance and no support for DV, HDR10, or some 4K (bitrate dependent).
Some boxes get around this by modifying Kodi so it calls the hardware player for local playback (e.g. Himedia+wrapper or Zidoo ZDMC).
The changes needed are detailed here: https://kodi.wiki/view/HOW-TO:Use_external_players_on_Android
This (paid) app does the the same with more options but I'm not sure it would work with Dune: https://play.google.com/store/apps/details?id=hu.xmister.xbmcwrapper&hl=en&gl=US
I'm not sure either of the above will work on Dune.
Has anyone got external player to work with the new Dune boxes?