I'm having same issue since the new ep of Servant dropped. On Unifi 800MB package. Every other streaming service works flawlessly but I can't watch any Apple TV+ show or any of my iTunes movies or TV Shows (US or Malaysia store). Can't even watch trailers so it's not an account thing. If I'm on data I can view iTunes movies/TV on my phone. If I try on wifi it will load ask 'Resume' or 'Start from beginning' then forever loading before popping out a 'There's a problem loading this content' on ATV4. It's just black screen on iTunes or iOS devices. Have reset router, gateway repeatedly. Use paid DNS, google or auto no difference. Is Unifi blocking Apple? I was going to call them up ask what's up cause this is new.

There's an underground/water cable issue? Maybe that's it. It's only since Thu or Fri evening but it is annoying. I can download the movie in iTunes at a decent speed (no slowdown) but it will not stream on any device (PC, tablet, phone, Macbook, ATV4 or ATV3). That kinda makes the ATV useless at this point. I livechat with Unifi so they reset my port but that didn't do anything. They ask me to do a pingplotter trace route thingy but not sure what I'm looking at ... oh well hopefully it is resolved in a bit. Really wanted to watch that Servant episode.

It works fine this morning on phone and ATV3 so maybe they had enough reports to get it fixed.   

Anyway now that most shows are almost done what's the new upcoming show to watch?

Edit - never mind, it's not working on ATV4k despite not changing any settings. What an annoyance but at least it works on other devices.

Managed to watch Servant this evening straight through then rented Joker but it won't play right on the ATV4k. Had to bring the ATV3 to use instead and it plays fine. Such a weird issue. It's intermittent off/on within an hour or two. TM called also late evening and said they did testing on my line/port and no issues on their end but said if I still have issues to clear cache, restart browser etc which means they don't really understand the issue. Sorry for kinda OT in this thread.

It only starts around 6-7pm. Can watch few episodes of the Knick in a row (Apple/iTunes TV shows purchased) then once that time kicks in it will start to get funky then eventually buffering/never play. So rest of evening switch to watching other things not on iTunes.

I do use a VPN (g-flix) for Hulu, Prime, Disney+ and it is set on each device individually. I can switch it to default, reboot router and iTunes still won't work at that specific time.

Do not have IPV6 activated. Should I? Have no issues before last Friday for years at this point. Same settings, rarely reboot router maybe once every 2 months lol Unless got issue of course.

Got a refund for rental of Joker no questions asked, despite the issue only being watching it on HD instead of 4k and messing up the flow of the movie for start/stopping.

Well on the Apple Support forums/community there are a few people having issues as well. Not in Malaysia only. It is intermittent and at certain times, which sounds familiar. Right now mine will go out most of the evening, on all devices. Most of the day the ATV4k will not play any movies/TV but the ATV3 next to it will play it fine. Of course until a certain time in the evening. It's baffling and hugely annoying. Am unable to watch any ATV+ series to catch up in the evenings. I just want it to work like it should. Good luck on your end too.

Oh gosh. I’m having the same issue as well. For the past few days i can’t seem to stream movies or shows from itunes and appletv+ shows via ANY of my apple devices (Apple TV 4K, iPad, iPhone and my Mac). Trailers doesnt stream too.  And i’m using unifi as well. But when i change to my Data, it works just fine.

I’ve tried factory resetting my apple TV but still the same issue.
However streaming netflix and amazon prime works flawlessly.

Should I lodge a complaint to Unifi too? At least for them to know its not an isolated issue.