Stuttering video in Plex for Kodi "PM4K" after pausing or rewinding the video caused by OSD

[evertonmdz]

In Plex for Kodi “PM4K” Addon. When I pause, or click to rewind a few seconds of the video, sometimes the video causes stuttering, which only restarts Kodi to stop the stuttering and then returns to normal. When I use “PlexKodiConnect” this never happens. Which uses the default Kodi player.
It has some relation with coreelec too, because on normal Android this never happens.
This only happens in PM4K, in the standard Kodi player, there is no stuttering after the OSD disappears.

Tox3 S905x4/c2

[liquidion]

no log no problem

also, when problematic content is playing, post the output of:

cat /sys/devices/virtual/amhdmitx/amhdmitx0/config

when SSH’ed into the box

[evertonmdz]

Thank you for posting that the solution is in the NG version, actually, I tested it here “CoreELEC-Amlogic-ng.arm-21.1-Omega_nightly_20240714-Generic.img” the OSD stuttering problem doesn’t happen anymore, yes, I knew it wasn’t a problem with PM4K, but as I said something in PM4K I didn’t understand that the OSD had been closed and caused eternal stuttering. It was a problem caused by a bug in CoreElec itself. I’ll keep using the NG version until the OSD stutter correction patch for NE and NO comes out.
I currently have this log.
log-2024-07-04-17.57.08 (1).zip (4.1 MB)

[sonofdibnah]

@evertonmdz

Thank you for posting that the solution is in the NG version

Has there been some private discussion on the topic because there’s no post about it in this thread?

[evertonmdz]

In oficial add-on GitHub Stuttering after pausing or rewinding the video in CoreElec · Issue #123 · pannal/plex-for-kodi · GitHub

[liquidion]

It is the incorrect color bit issue that was patched here:

Dolby Vision for Minix U22X-J (Max) and Ugoos AM6+

@liquidion please update with this test build and try again if it now works correct: Please make a log with these commands again after update with this test build: dmesg -c echo 3 > /sys/module/amdolby_vision/parameters/debug_dolby -> start playback in kodi and stop it again after 2-3s of video visible on screen dmesg | paste

One of the symptoms is content stuttering once OSD is activated during playback. But it seems like this is still an issue on NE, not sure about NO

[sonofdibnah]

Thanks for the info. I’ll have a good look at NO later to see what it does. I’m using PM4K path mapping. Am I right in thinking that the stuttering does not happen with path mapping? I’ve read a lot and understood bits.

[liquidion]

It will happen with path mapping as well. Iirc someone tested that on the PM4K thread before the patch was released, and it still had OSD stutter issue.

I believe the root cause was how the Kodi video player was invoked rather than the specific format.

PKC uses plugin handler, PM4K uses https/smb handler:

CE-NG Dolby Vision for G12 boxes (u22xj, am6+, firetv cube)

That makes sense re: why the TV seems apathetic to the incorrect bit selection. I’ve been doing a bit more digging into this issue and chatting with the PM4K creator. Just a quick high-level summary. There are 2x apps that extend Plex onto Kodi. They are PM4K (PlexMod4Kodi) and PKC (PlexKodiConnect). Both are capable of SMB path substitution to directly play the content. However by default, both utilize the webstream method where it passes the stream URL generated by Plex into the internal pl…

HTTPS/SMB handler has a slight difference in timing vs plugin handler. This post from Portisch explains more:

Dolby Vision for Minix U22X-J (Max) and Ugoos AM6+

It’s a knowing timing issue. Not sure yet how to solve it… When it works: kernel knows it’s DV, set display mode 0.5s after that → 8bit When it does not work: kernel does not know it’s DV, set display mode, kernel knows 0.5s after it’s DV → to late → 12bit

[sonofdibnah]

Thank you again for the background info. I tried New Order CoreELEC last night by pausing, jump skipping, enabling/disabling subtitles and stop starting on multiple videos but I couldn’t see anything amiss.

I’m on s905x4, PM4K 0.7.9 beta 13.2. Hopefully this means it’s fixed but I note that the stuttering is occasional.

[evertonmdz]

I tried using NO too, but when opening the OSD it still stutters, so occasionally it will cause eternal stuttering. Having to restart kodi to fix it, the only stable version without stuttering in the OSD for me is NG. I’m on s905x4, PM4K 0.7.9 beta 13.2 too.
Just to be clear, eternal stuttering doesn’t happen every time.
LOL
I just noticed that when there are subtitles on the screen, ASS or SDH for example, when you open the OSD there is no stuttering. It seems to have something to do with the subtitles.

With SDH subtitle enable, without OSD stuttering:

Without subtitle, with OSD stuttering:

I don’t mind having OSD stuttering, but this OSD stuttering causes eternal stuttering in PM4K almost every day.

log-2024-07-17-13.41.47.zip (4.1 MB)

I added this dialog line in the advancedsettings xml file and it apparently resolved the OSD stuttering

  <gui>
    <algorithmdirtyregions>0</algorithmdirtyregions>
  </gui>

S912 Subtitles stutter fix - Kodi - CoreELEC Forums

[sonofdibnah]

I’m going to have to live with this i think…Reason is that on S905x4 I need NO for live TV channels to play properly through TVheadend.

I hope the developers see something in your log that helps them incorporate a fix into NO.

[evertonmdz]

Have you tried adding the dialog line in advancedsettings.xml? This solved the stuttering problem.

<gui>
    <algorithmdirtyregions>0</algorithmdirtyregions>
  </gui> 

[sonofdibnah]

Yes, I’ve added it and I’m just going to run with it like that and see what happens.

[sonofdibnah]

I didn’t run for long. I’m back on NG too until it’s fixed in NO.

[evertonmdz]

I had no more problems in NO and NE after adding this line of dialogue.

[sonofdibnah]

Mmmh. I agree with you now. In a somewhat slapdash fashion, I’ve ignored the good result with S905x4 and assumed that problems encountered with NO on Odroid N2 (S922) are the same. The latter is a different issue.