[Puni]

Hi there,

i recently got a Fire TV Stick 4K Max Gen2 and video playback isn't really smooth on Kodi. Initially running 20.5 but also gave 21.0RC2 a try.
My main use-cases are the Youtube Plugin and Tvheaded, so i currently don't know if my issue also applies to locally stored video files.

It's most noticable on channels that have a newsticker running (i.e. German public broadcast service "tagesschau 24").
TV broadcasts here are 50Hz so that's where is observe this issue the most. Automatic Refresh Rate is enabled in Fire TV settings and Kodi (Always, Start/End, doesn't really make a difference). All refresh rates for the displays' native resolution are whitelisted in Kodi settings. Kodi UI is set to 50Hz, but other values don't seem to improve the situation.

Kodi OSD and TV report the correct refresh rates the whole time.

By chance i found a workaround which isn't the most practical though.
If playback is stuttery one can
- bring up the Settings menu
- "Select Resolution"
- select a different refresh rate
- switch back to target refresh rate
-> smooth playback

What also works is setting Kodi UI to a different refresh rate from the video and have "Adjust display refresh rate" set to always. Then, during playback, switch to Kodi UI and then back to fullscreen playback. After a few seconds playback will be smooth. But this is only applicable if UI and video refresh rates are different from each other, which with Youtube isn't a guarantee.

My Fire TV Stick 4K Max Gen1 which I normally use on another TV set works flawlessly.

Anybody else experienced something similar and maybe has a more robust fix (setting) I can try, before I collect logs and open a ticket?

[Puni]

Opened a ticket ( https://github.com/xbmc/xbmc/issues/24904 ) but it got closed rather quickly.

Maybe I should have followed their advice and first asked for support on this forum.

[robbie599]

Have you tried Automatic Refresh Rate enabled in Fire TV settings, and in Kodi: ‘Adjust display refresh rate = Off’ (instead of ‘Always’, or, ‘On Start/Stop’).

[Puni]

Have you tried Automatic Refresh Rate enabled in Fire TV settings, and in Kodi: ‘Adjust display refresh rate = Off’ (instead of ‘Always’, or, ‘On Start/Stop’).

Tried it just now, but unfortunately no improvement.
Same with the other way round ( adaptive refresh rate off in Fire Tv settings and on in Kodi).

[jogal]

Recommended Kodi settings are:

GUI resolution 3840x2160 or 1920x1080 at 59.94 Hz     (you have 50 Hz!)

Adjust display refresh rate = at Start / Stop

WHITELIST:  Selected all 3840x2160 modes ---> 23.976, 24.0, 25.0, 29.97, 30.0, 50.0, 59.94 Hz

Then since GUI is 59.94 Hz and videos (TV channels in your case 25/50 Hz) switch refresh rate will work (at Start/Stop)

For movies (23 or 24 Hz) should also work...

[Puni]

Recommended Kodi settings are:

GUI resolution 3840x2160 or 1920x1080 at 59.94 Hz     (you have 50 Hz!)

Adjust display refresh rate = at Start / Stop

WHITELIST:  Selected all 3840x2160 modes ---> 23.976, 24.0, 25.0, 29.97, 30.0, 50.0, 59.94 Hz

Then since GUI is 59.94 Hz and videos (TV channels in your case 25/50 Hz) switch refresh rate will work (at Start/Stop)

For movies (23 or 24 Hz) should also work...

Sorry to say, but that didn't help either.
I can see from Kodi and TV OSD that it indeed switches from 59.94 Hz to 50 Hz but the microstutters still happen. I can only get a smooth stream if i once manually switch refresh rates back and forth during playback.

After doing this the problem seems to be gone even after restarting the stream (at least for this refresh rate). However it shows up again after restarting Kodi.

[fritsch]

Does it help to put run kodi in 50hz? In general?

[Puni]

Does it help to put run kodi in 50hz? In general?

So far i tried running Kodi at 50 Hz, 60 Hz and 59.94 Hz recommended previously without much success. There are a few other refresh rates I can also try out if you suggest so, but i hardly believe that these will bring an improvement.

Just observed this now, don't know why I haven't noticed it earlier. Kodi UI itself seems to stutter lightly after a restart, although it is hard to notice. Saw it by chance while the Whitelist setting was scrolling from right to left.
The workaround also temporarily fixes this.

So maybe this isn't a problem with the refresh rate itself? It might 'just' be something that gets fixed by chance when you change the refresh rate manually?

[w8andc]

Since a few days I am also owner of the new Fire TV stick 4K Max (2nd gen). I come from the old Fire TV stick 4K (2018).
It was some challenge to setup this device including ethernet cabled internet connection and extra 120 GB USB external storage.
But all is setup and running now.

Use this device to watch live TV from satellite through the DVBviewer PVR add-on in KODI. 
Installed a recent KODI nightlies version  v21 (kodi-20240326-e70f0d83-master-armeabi-v7a.apk)

Also saw obviously microstutter in KODI. No fluent video at all.
Was surprised because on the old Fire TV stick 4K and the same KODI v21 didn't have this problem.
Tested this also through the Youtube app on this device (not KODI). Then video image is very fluently. No stuttering.

Something in KODI.
I tried many settings without success.  In the end I came to the conclusion that the setting "Adjust display refresh rate" turned to "Always" solved the problem.
In this case Kodi and the TV screen more often changing resolution / refresh rate automatically in contrast when propertie is set to "On Start/Stop".
This results afterall in a very fluent video image.

[fritsch]

Sorry to say that: Android devices are the wrong choice for DVB-S content. Deinterlacing in 2024 is a hit or miss. It either works or not at all. The code that works for your 2018 FireTV is exact the same run for the newest variant. Even worse: It's an entire blackblock on Android ... so we cannot even fix something there.

Are all channels affected? 720p50 as well? 576i also?

[Puni]

For me all content seems to be affected, HD, SD, interlaced, progressive, DVB-S, Youtube Addon…
But as said: once I changed refresh rates often enough, stuttering seems to be gone until the next restart.

Sidenote: From my experience 4K and 4K Max Gen1 Fire TV Sticks are OK-ish with interlaced DVB-S stuff, at least with tvheadend backend. The only thing to note is that Bilinear deinterlacing is the best one can hope for.
Was previously using RPi 3 / 4 which had more issues. Like when there was an aspect ratio change mid-playback among, other stuff that annoyed me.

edit:
So i relegated the Gen 2 Stick to a TV set i don't use that often and while setting it up I noticed some further things.
As previously mentioned the microstutters also affected the UI but I noticed that it would only do so at 50 Hz. If i set Kodi to i.e. 59.94 or 60 Hz the UI works smoothly.
Also video playback was smooth as long as it was not 50Hz (and the one strange DVB-S channel that reports 25 Hz).

I wouldn't believe that kodi would have some special code to handle 50 Hz (ar not-50 Hz). So increasingly more likely to be an issue to Fire OS 8 / Android 11 / SOC Firmware.
SOC betwenn Gen1 and Gen2 doesn't seem to be that much different. Firmware can still be different though.

Thanks to everybody who tried to help so far.
I guess the new FireTV sticks are not (yet) suited that much for Kodi. Maybe a future OS update will help.