I've had no 6 Series 65" for 14 months and for the last 6 months or so it will just reboot. A full reboot that takes minutes to come back. I believe it only happens when using the HDMI ports (My Xbox or PS), I don't think it happens using native apps. The TV is update to date and I haven't had any other issues or seen this on any of my other 6 TCL TVs. I even swapped out the HDMI cord for a new 2.2 one that came with the Xbox Series X and it happened within 5 mins.
@EverlyWyatt wrote: I've had no 6 Series 65" for 14 months and for the last 6 months or so it will just reboot.
I'm sorry you're having this experience. There are other threads about it. In your case, it started when you had the tv at 10 months? Did you try to assert a warranty claim? That was your lifeline (compared to what you face here). If you did, and TCL pointed the finger at Roku (to evade its responsibility to you for the product it sold to you), you could still get some help that way.
1. One thing which might help is the so-called "clear cache:"
Hit HOME 5 times. UP once. REWIND twice. FAST FORWARD twice. (Clears cache & tv reboots itself. Be patient. It takes 2-3 minutes for the tv to go black, and come back on)
That has been shown to fix strange Roku software problems which other similar self-help activities don't. It's worth trying.
2. You could also factory-reset your tv, BUT... during the setup, tell it you'll connect to internet later. This seems to cause the tv to run a lighter, seemingly older version of software. The Antenna-TV UI looks older (it had favorites again, continuous channel changing worked again).
The idea here is: use the tv as a dumb tv, stream through HDMI. If the problem stops, just never connect to the internet again. (That's what I've done with my two regrettable Roku TVs. I've seen others say they've done the same thing to have a better tv experience.). Plus, you'll protect your tv from future untested Roku updates which break tvs, and Roku disavows any responsibility. You can't go back to a previous working version (like you can with Android TV).
3. I don't want to discourage you. Maybe other "tricks" would fix you. But, if you look back through pages of this forum, there's not a lot of hope that Roku will engage with you. They blame the tv maker at every oportunity (their software update as breaking tvs, and Roku kept pushing it out while blaming the tv makers. They even ridiculed customers in a Business Insider article about the "clear cache" thing. Everyone's having problems. Some people really have been fixed by that thing which is very different than an ordinary restart. But, all Roku would contribute was "there is no cache [eye roll, silly customers]" loose quotes. Here we are, 8 months later, and things are worse. But, in Rokuland, the important thing is for us to know there's no cache. Not what the problems are, or if they'll ever be fixed.).
So, you should accept that you're probably going to have to buy a new tv. There's a lot of people who have been waiting months (years) for nothing, wasting their time. There's no formal bug tracking. Just "we've passed it along" (or "reach out to the tv maker."). Problem reports are treated like casual suggestions. "Thank you." So, you might as well orient yourself to that (as Morpheus called it) "the desert of the real."
If you like to fiddle with things, you could replace the boards in the tv. About $70 for your higher-end model (probably). ShopJimmy sells all the boards in a group, or individually.
The weird thing about this is: if you were under warranty, TCL would be responsible for fixing the problem. And, there are reports of TCL fixing these problems (even the ones that are clearly caused by Roku's software updates). That implies there's some kind of hardware ambiguity. It's not just the software update. Perhaps TCL has different revisions of boards (different chipsets). Nobody knows. Roku won't explain what it surely knows about the situation. But, the risk for you would be that you'd get the same boards. Nobody will tell you what's compatible with Roku's software, and what isn't. Or, you might just have a bad board, and then get a board revision that isn't compatible with the latest untested update.
So, it would be a gamble. If you like fooling around with things, you might pop for $70. Have some fun. But, if money's tight, that could easily be throwing good money after bad.
"People are often amazed at how much we’ve done with the number of engineers we’ve got." (Roku CEO Anthony Wood, Austin Statesman, Oct 4, 2019). "Amazed" is one way of putting it.