UPDATE:So, this is potentially good news for Tino.
I will also bring up that I and quite a few others had problems with Sony's 4k bonus disc of "1776" playing in the UB820.
Well, this is interesting. I have two Panasonic UB820s. Both were purchased at around the same time a few years back, and both are updated to 1.69 version of firmware.
The only difference is, one of them will not play any of the Avatar: The Way of Water Blu-ray discs from the 3D set. The other plays them all perfectly!
I will have to do some more testing to find out if it has anything to do with what TV or monitor is hooked up to the player, or any other settings in the player or TV that might be different.
WEIRD!