[superczar]

I thought of starting to use Kodi again after probably a decade or so.
I setup a USFF Lenovo PC with a i5 9500T and a Quadro P620 card to the task with the intent of 4K HDR and (sometimes) SDR playback

However have been facing some odd issues with this setup

HDR and SDR playback:

With frame rate matching on, HDR playback works great.
Windows display settings HDR is set to off and the display switches to HDR once playback starts. 24hz videos playback at the native framerate as expected

However with this setup SDR playback has highly elevated Blacks (i.e. Blacks look gray)
Once playback starts (for a SDR file), the initial black screen first turns gray and then subsequent playback has wrong black levels
The same file plays with the correct black levels on other apps like VLC

If i turn off frame rate matching, this problem disappears (i.e. SDR playback is normal) 
but in this case, HDR switching does not work (i.e. HDR file plays with the display staying in SDR and renders wrong colors)

Frame skipping

Kodi 19 has flawless playback
Kodi 20 and 21 skip 4-5 frames (as confirmed by the playback HUD) every few seconds

I eventually ended up installing 19 and then did a portable install for Kodi 21 and surprisingly the portable install worked fine with no frame skipping
This is  currently resolved with this workaround but am curious why this should be the case


Log attached with two file playbacks.. One HDR (which worked fine) followed by SDR (with raised black levels)
https://paste.kodi.tv/obiwahuxeg.kodi

[CrystalP]

Kodi is doing things correctky in that log.
There is no difference in black processing in Kodi with or without refresh rate switching, so maybe your TV has different settings per resolution/refresh rate/hdr-sdr mode and needs an adjustment to the range.
You don't get the raised blacks with Kodi 19 and frame rate switching?