Originally Posted by yaxasdad
Sony KDL-55XBR8 LCD TV Specifications
Screen size: 55"
Pixel resolution: 1920x1080
1:1 mode at 1080i/p? Yes
Accept 1080p? Yes (24, 60)
Display 1080p/24 at: 120Hz
Refresh rate: 120Hz
It was the flagship of the Sony line when it was produced (2008-2010). It is a a full 1080i/p HDTV. I have the Roku connected to the #4 HDMI port after trying it on #3. I have a LG UBK90/80 4K UHD Blu-Ray Player connected and it streams Netflix without any difficulty with a clear image. For the LG Blu-Ray player and the Roku I am using 4k high speed cables purchased through Monoprice.
Without diagnostic devices that actually let you see how the handshake is going and/or measuring the signal, most HDMI troubleshooting is a lot more country/witch doctor than most want to admit.
I have an older 720p TV of a different make.
From my Roku 3 it will accept 1080p (presumably 60, since I don't have framerate matching)
From my Roku Ultra (4640) it will not accept 1080p, but the Roku, if allowed, will auto set the resolution to 1080i (which is probably expected behavior)
Since it looks like you don't have a problem with the current TV picture or "upgraditis" for the TV, I would suggest just try some other resolutions manually, or if you are using manual, try out Auto on the different inputs.
Or, if you are otherwise OK with the picture but just won't be able to stand it knowing the devices picked less than the "best" option, have your spouse (or other non-invested party) do that function and if it gives a decent picture, just don't look in the settings.