My Sling TV app is also 8.11 build 1669, and my Prime Video app is also 12.0 build 2021090212.
My Roku OS is 10.5.0, build 4201-95
I could be mistaken, but the first four digits of the build are what's important. The digits after the dash are supposed to not matter, and they can vary depending on the device. My Roku Ultra actually died this week after four years of service (model 4660), so I'm on my Streambar. I'm sorry I can't do an exact compare.
Regardless, my Roku running 10.5.0 b4201(-95) and the same Sling TV and Prime Video app versions. That will make this hard to resolve. Now, it may end up resolving itself, but in the meantime, anything we can do to speed that along would be something to try.
There are actually two differences in our setups. One is obvious, and the other not so much. And neither may make a difference, but with a head scratcher like this one, it may be that something unexpected is the issue.
The first obvious difference is that I'm on a different Roku device. You have an Ultra 4670 running the same OS, 10.5.0 but the build has a slightly different number: 4201-46 vs my 4201-95. Again, my understanding is the digits after the dash on the build don't really indicate a difference in code, but is related to the family of devices. Still, that's something that @RokuDanny-R or @RokuKariza-D can address.
The other difference is not so obvious, and I tested it. I bring it up in case others following spotted it and wanted to pursue it. I don't have Netflix. The thought behind this was that one app was causing an issue with another app. So, I added Netflix to my Roku, logged in (family member account), and then I rebooted the Roku. By the way, Netflix 5.1 build 98088456
My test showed everything working. All three apps run just fine for me.
So, what's the difference? Why are you having issues and I'm not? I'm at two schools of thought on this. Perhaps something will trigger in your mind, or perhaps someone reading this may have a thought we can pursue.
There is the difference in the build suffix, your -46 and my -95, which I believe corresponds to the difference in your device (Ultra 4670) and my device (Streambar 9102).
The other difference could be some glitch in your device that happened around the time, or perhaps because of, the update to 10.5. I'm guessing that's when this began, based on others' complaints.
You've restarted the Roku.
I'm not sure if you removed the troublesome apps, rebooted the Roku, and reinstalled the apps (gotta be in that order: remove, followed by reboot, followed by reinstall), but that may be worth a shot. I don't hold out high hopes at this point, but still it's something that should be ruled out.
I hope that @RokuDanny-R or @RokuKariza-D can get some additional information from you and get their team on this.
The problem is that most people don't have the issue. Yes, there are a lot of people posting here about it, but with the huge number of Roku users, it's a very small percentage with the issue. However, the issue is happening, and it needs to be resolved in some way.
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