Hi! I initially posted this problem on the Yamaha thread on AVS Forum, but was unable to resolve the issue through my receiver settings. It was suggested that I investigate whether the issue lies with my ROKU settings, so I wanted to post here.
I am trying to set up my new Yamaha TSR-7850 receiver, but am having problems with ROKU video pass through. Currently, I have a ROKU Ultra plugged into "HDMI input 2" on the receiver and the "ARC HDMI output" on my receiver is connected to the "ARC HDMI input" on my 2018 Vizio P75 TV. The TV recognizes the receiver as it has renamed the input to "TSR-7850," however the TV says "TSR-7850 is connected to HDMI-1. TSR 7850 has no video signal." I can hear the ROKU audio through the speakers connected to my receiver, but the TV does not receive video.
A few observations that may be helpful:
Attaching the ROKU directly to the TV using the same HDMI cables (without utilizing receiver pass through) works without issues.
Changing the ROKU to other HDMI inputs on the receiver does not help.
Video from my 4K LG Blu-ray player passes through correctly through all HDMI inputs on the receiver. When I check the video "Information" screen on the receiver, it confirms that both video input and output from the Blu-ray player is 4K at 60 Hz. I tried removing the HDMI cable from the back of the working Blu-ray player and plugging it directly into the ROKU, but this does not work and the screen changes to no video input.
For working video inputs (e.g. Blu-ray) and audio-only inputs (e.g. tuner), I can display the receiver settings menu on the TV screen by pressing the button on my receiver remote. However, when I'm trying to view the ROKU and the screen is black, the menu does not display (the receiver screen still displays "View On-screen" indicating that the menu should be visible on the TV).
Strangly, when I reboot the ROKU, the ROKU boot screen does show on the TV (the screen that shows bouncing letters that spell "ROKU"). However, once this boot screen should change to the usual ROKU menu, the video output stops and the TV screen appears black. During the ROKU boot animation, the video "Information" screen on my receiver shows both input and output as 720p at 60 Hz. When the boot animation ends, input and output change to "???".
Unplugging and replugging the HDMI cable in the back of the ROKU does not fix the problem. Unplugging and replugging either of the HDMI cabless on the back of the receiver also does not fix the problem. However, unplugging and replugging the HDMI cable on the back of the TV usually does resolve the problem, resulting in a properly displayed image (this is what I'm currently doing each time I want to watch the ROKU). After doing so, the video "Information" screen on my receiver confirms that the input and output are again 4k at 60 Hz.
I've wondered if the problem lies in the ROKU's "Display Type" settings. After unplugging and replugging the HDMI cable in the back of the TV, so I can view the video output, I looked into this in the settings. The default option in "Display Type" is set on "Auto detect." The ROKU correctly reports that it has detected a "4K HDR at 60Hz HDCP 2.2" display. I tried manually changing it from "Auto detect" to "4K HDR 60Hz TV" selection and it continues to work properly. If I unplug and replug the HDMI cable in the back of the TV, I get the message that "Your display type has been reset to automatic," and the display continues to work properly. The "Display Type" settings still correctly report that a "4K HDR at 60Hz HDCP 2.2" display has been detected. However, as I've experienced previously, if I leave the TV/ROKU idle for some time (such as overnight), the video output no longer works. I'm suspicious that the ROKU's display "Auto detect" is not working properly after it wakes from standby. Unfortunately, it refuses to keep my manual display settings. When the video output was not working correctly, I tried hitting the proper button sequence (home-up-right-down-down-down-down-right-up-OK) on the remote to manually switch the display back to "4K HDR @ 60 Hz HDCP 2.2," but nothing changed on the screen.
I also have a few other ROKU boxes that I decided to try. First, I plugged in a ROKU Premiere+ which behaved the same as the Ultra (the 720p boot video displayed correctly, but the screen when black after the ROKU should have switched to the 4K app menu). I then plugged in an older ROKU 3 which outputs video in 1080p and this worked with no problem (confirmed 1080p video input and output in the video "Information" screen on the receiver). I then plugged the cable back into the ROKU Ultra with no luck. I then decided to plug the cable back into my 4k Blu-ray player and it works fine again (confirmed 4k @60 Hz video output on the receiver menu).
In summary, when using my receiver's video pass-through the 720p ROKU boot video displays correctly, but the video output stops when switching to the ROKU app menu which should display in 4K at 60 Hz. My older ROKU passes 1080p video correctly, including the app menu, so it's not a problem with all ROKU's in general and seems more related to 4K ROKU output. My ROKU Premier+ exhibits a similar problem as the ROKU Ultra, so it's not a problem specific to the Ultra. However, my 4K Blu-ray player works as it should, so it doesn't seem to be a problem with 4K resolution in general. I'm wondering if it has to do with the video output settings on the ROKU (it keeps reverting to "automatic" even when I manually set it to 4K HDR @ 60 Hz), but blindly hitting the button sequence to manually switch to the proper video output doesn't solve the problem. The only thing that works is unplugging and replugging the HDMI cable in the back of my TV. Is there a way to prevent the ROKU from reverting back to auto-detecting the display type? I would love any advice to resolve this issue as I'm running out of ideas!
Roku boxes have some issues with passthroughs but there are a couple setting adjustments via the secret screens to help you. Two things to do to fix the auto-detect revert: Turn off the screensaver and disable automatic recovery (5X Home, Down, Left, 3X Up)
Thanks for the reply. I think I've found the problem with my setup. My Vizio TV has a setting that can be enabled/disabled for each input called "UHD Color." This setting my be enabled to display video from my Roku, but must be disabled to display video from my 4K Blu-ray player. My current workaround is to plug each device directly into the TV inputs, so each input can have the proper "UHD Color" setting selected. The audio then passes to my receiver via the ARC HDMI line. I was hoping I could pass audio and video through my receiver, but this unfortunately does not appear to be possible with my setup.