first post here, despite I've been in the Roku family for the past 12 years.
Suddenly, my 4 year old Roku Ultra started having intermitting blackouts. I thought my TV was failing (an old Sharp Aquos, LCD 1080p), but I verified that no signal issues occurred when connecting the TV to my Macbook via HDMI. I then assumed my Roku was failing and ordered a new Ultra. In the meantime, the old Roku completely died.
This afternoon I received the new Roku and, after a flawless setup, the same flickering on the TV occurred. I changed cable, I changed input on the TV, yet the problem is still there.
I did try that, but unfortunately it has not solved the problem. I noticed though that if I do no action on the remote when on the home page, the image is stable. When, instead, I scroll the menu or start Netflix (I haven’t tried other channels yet) there’s these intermittent blackouts. It looks like changes in video/sound bother the system.
Assuming you are using the provided PSU for the new Ultra (and not the old one) the fact that two different Roku models with different SoC's (but likely the same firmware) have the same problem likely indicates either a firmware issue (HDMI sync/EDID issue) or a TV issue.
You should test the Ultra with a different TV - if it doesnt exhibit the same behavior, you know its an issue with the Sharp TV.
Having seen similar scenarios with older TVs and Rokus in the past, you might consider a Factory Reset of the TV (its resolved many odd HDMI issues with Roku devices).
1) Change to passthrough audio mode: Settings/Audio/Digital output format = Passthrough ("Auto" by default)
2) Disable framerate matching: Settings/System/Advanced system settings/Advanced display settings/Auto-adjust display refresh rate = Off (Off by default)
It seems my earlier reply got lost, so I’ll post again. Apologies for the repetition in case my message appeared successfully.
I did try to follow your recommendations, with the exception of assessing hdmi transmission: unfortunately I was unsuccessful.
I originally excluded a TV problem because my MacBook managed (and still manages) to transmit AV signals via hdmi to my TV. In the meantime, my old Roku died so, while waiting for the new one to be delivered, I was 100% sure the old guy got damaged.
With the issue appearing on the brand new one, though, I feel puzzled: the TV works fine with the laptop and the Roku works fine transmitting video to a desktop monitor via hdmi (I have just one TV so that was the best I could test).
I had done the factory reset of the TV already, but no luck. I thought the HDMI automatic recovery on the Roku would have been the key (I did not know the Roku remote had "fatalities") because, as a matter of facts, the intermitting blackouts I experience come with the TV right corner box informing me of input and resolution, but, again, no luck. This could though explain while streaming from the computer is instead flawless: a difference in HDMI information?
Anyway, it seems my only solution would be replacing the TV as well...
Yes, generally speaking computers use a different HDMI video colorspace format (RGB 4:4:4) than Rokus/etc (YCbCr 4:2:2 or 4:2:0), though these things may be changed/tweaked depending on specific device/hardware/OS/driver versions.
1) If there is any ability to change the HDMI mode/settings on that Sharp, you can always play with those and see if they result in anything different.
2) You might also check to see if you have the latest/there is a newer firmware available for that Sharp TV (model unknown).