all my devices are new 2017 models. Everything works fine if I wire from the blu-ray player to the TV, but if I add the 976 between the two I’m having issues. The reason I bought the 976 was to handle older dvd’s & blu-rays from my collection and 4k blu-rays going forward. I should not have to limit my TV for the 976 to handle the video.
I don't have that TV obviously, but I have the Oppo 203. I'm not having any issue, paired with the 976, for any discs I play.
I was thinking of the HTPC you mentioned maybe not being compatible with HDMI2.0a, or even the standard mode on the Sony.