[Sunflux]

Did you enable the "Limited Range" Option in XBMC? In my case (Panasonic TXP50GT30) only with Limited Range Option enabled the Output is not clipped...

No, that makes it even worse. The workaround was to put

xrandr --output HDMI1 --set "Broadcast RGB" "Full"

in the autostart.sh script. Now it outputs RGB 0-255 for the GUI and video and there's less banding / posterization in gradients.

After much real-world testing with gradient patterns, the absolute BEST quality video reproduction (at least on a gradient basis) comes from the following settings:

* OS forced to FULL RGB output range
* Kodi forced to LIMITED RGB output range (via menu setting)
* Television forced to LIMITED RGB output range.
* "Prefer VAAPI Render" DISABLED (yes, disabled - enabling it will actually result in significant clipping)

All other scenarios involve forced conversion of 16-235 to 0-255 (and sometimes back again) and, alas, this conversion process introduces significant banding into gradients. To be fair, for general usage you might not notice the difference.

The only way to get proper limited output range while using VAAPI is with this:

* OS forced to Limited RGB output range
* Kodi NOT using the Limited menu option
* Television set to Auto or Limited RGB output range
* "Prefer VAAPI Render" ENABLED

Note, however, that this involves dual range conversions - a video's native 16-235 is forced into 0-255 by the VAAPI Render option, then converted back to 16-235 for output. This process does not seem to be seamless.