As far as I know Plex does do refresh rate switching so that would be fine, might need to enable it in the settings though.Hi, yes I have a C9. I have been using Plex. Do you know if that does the same as Kodi?
I use an excellent little app called Refresh
Rate from the Play Store. This allows you to set frame rate for particular apps.
I use this to set BBCiPlayer, ITV Hub and My 5 so they all start at 4k/50hz (native UK framerate). 50hz does not go into 120hz cleanly so it won't look right.
Most other frame rates do though which is why the default 4k/59.94 works fine.