[Boulder]

My TV supports 24p, 50Hz and 60Hz modes at least according to what I've seen on its OSD when checking the refreshrate. So "standard" framerates would be 23.976, 24, 25, 50 and 59.94 fps.

Using advancedsettings.xml to put everything encoded at 23.976 fps to refreshrate 24 fps, the "debug" display shows 24 fps while playing the video but my TV stays in 60Hz mode.

No - don't do that. That will render passthrough unusuable. Your TV lies about its refreshrates. DISPLAY=:0 /usr/lib/kodi/kodi-xrandr | pastebinit tells what it really supports.

This is what I got: http://sprunge.us/iChF

Please note that the information comes from my receiver, which should passthrough 24p fine because the Mede8er was able to use that output format. I'm using a Lindy EDID emulator between the Chromebox and the receiver due to HDMI handshake issues, but the EDID data was cloned from the receiver when I installed the device.

Thanks for any help!