Chapter skip broken since March 2022 update (only mkvs with Atmos/DTS-X audio affected)

I recently noticed issues with chapter skip - apparently introduced with the March 2022 release as all versions forward incl. October 2022 release do show this issue. The issue is similar to what was reported in 2019 here

Some chapters can be jumped to in the bookmarks bar, but for some (always the same ones but different ones in diferent videos) it just skips to beginning of the video and playback is frozen even though the time counter increases each second beginning with 00:00:00. Issue also happens when skipping subsequently chapter by chapter with the next chapter button.

Did anyone else notice this issue?

Hi,

I remember the changes made after the report in the link that you’ve referenced – but I’m not sure that the change is still relevant.

I wonder if @spl147 or @MidnightWatcher can chime in and see if they’ve noticed a recent regression.

It would be very helpful if you could pin it down to a specific version. If you upload some logs, we should be able to see (approximately) which versions you’ve been upgrading from and to.

It would also be good to know more about which content works and which content doesn’t.

Sam

I can not say, i have moved away from this box, browsing my 1200+ movie collection became to much for the older chip and ram!

I have moved on to the khadas VIM3 running CoreELEC, very impressive hardware and rock solid software

Thanks for coming back to comment – I’m sure our commitment to support and future Vero devices will see your return in the future.

Sam

Hi guys, I captured logs in the meantime and did some more experiments.
From what I see in the log seems the issue is related to audio-sync and from my tests it appears the issue only shows for videos with 3D audio tracks, Dolby True HD / DTS-X. At least I was not able to reproduce the issue on videos with 5.1/7.1 Dolby/DTS tracks. Also notice that it is not always the same chapters being affected - at least after a reboot it showed same video had issue with a different chapter than before. The one I captured the logs for used to get repeatively stuck on chapter 13 - after the reboot it was 14. Strange…

When seek fails, it shows this line in large numbers:

2022-11-11 23:43:42.859 T:2873 WARNING : ActiveAE - large audio sync error: 7390060.549652

Attached Logs show seeking to 4 chapters via the Bookmarks bar in the video player. First 3 seeks were fine (Chapter 6, 12, 13), last one to Chapter 14 caused player to jump to
00:00:00 and video frozen.

@sam_nazarko Please have a look at my latest post with extra details and logs. Hope that helps to narrow down the root cause of the issue. Thanks!

These don’t look like full logs to me – they seem edited. I can’t do much with them.

Hi @sam_nazarko Yes, I anonymized the original log and removed stuff from before last reboot - didn’t expect it was important. But maybe I deleted some other stuff by this manual edit by accident. I did enable debug logs in OSMC, though. Please let me know if there is still something missing and what you specifically you are looking for - maybe I need to enable some extra log switches?

New log is complete but again anonymized. The test video I was referring to last time is now smb://c1e039d3cb1d50dadb506d8bca541de4.mkv

Thanks!

Seems this old issue showed exactly the same sympthoms: Freezing and problems when trying to skip chapters in mkv playback

Maybe a regression? Should I open a new issue against Kodi rather than OSMC? Did the latest OSMC updates include a newer Kodi version?

@sam_nazarko I have opened a Github issue for this now.

GitHub is for confirmed issues only. I will need an unmodified log and video sample to reproduce and resolve the problem.

Sam

Hi @sam_nazarko I did upload the full logs above. I just removed private information by removing sources.xml section and ran a small Python script to replace video filenames by its MD5 hexdigit. I would not expect these modifications to hinder problem determination for the given issue.

I did some more tests with HDMI audio pass-through disabled which interestingly leads to a different result: When skipping through chapters, instead of having the video freezing after some skips, it now shows a green screen which does no more go away even after stopping the playback. However, I can still hear the UI sounds when hitting buttons on the remote control so apparently it is not completely crashed. I am also able to initiate a reboot via ssh in this state. However, funny to see different results depending on HDMI pass-through enabled or not.

As mentioned earlier, I have seen the issue solely on Blu-Ray rips (makemkv) with a Dolby True HD/Atmos or DTS-X audio track. The affected files were created years ago and did not show the issue with older versions of osmc. That said, I am close to take the effort to revert my vero4k back to the March version of osmc…

So this log is from my latest tests with pass-through disabled.

Hope this helps to narrow down the issue. You have requested a sample video - well, not that easy without running into legal issues I guess… Maybe I can take a free Atmos demo video and add some chapters hoping it will also show the issue. Does this make sense to you?

What makes me wonder is that apparently no one else is facing this issue - maybe my installation is screwed up somehow?

Thanks for help!

Cheers,
Frank

Samples of media created for troubleshooting/testing of equipment are covered under fair use. There is no legal jeopardy there.

What I missed to say: I have also tested on Fire TV Stick 4k running Kodi 19.4 with same video files - no issues with chapter skips.

Once we have a full log and video sample, we can certainly look in to this.

I don’t think this will help. Usually we can get away with a small sample of the affected clip if it reproduces the issue or the full video entirely.

You could try a fresh install from Download - OSMC if you want to try this first.

Cheers

Sam

Hi guys,

so I reverted back to March 2022 doing a clean install via image. Chapter skip issue showed on this version, too. So I went back one more version to Dec 2021 and voilá - issue gone! So apparently the issue came in with the March 2022 release which also updated Kodi from 19.3 to 19.4. However, as mentioned the Android version (Fire TV) of Kodi 19.4 does not show the issue.

Anyway, I spent a couple of hours on this and do not want spend anymore time on it. That said, I will stick to Dec 2021 version - it has everything I need. Pretty sure others will report this issue, too, sooner or later - would be good to be fixed somewhen in time.

If you can provide a sample clip that’s affected, I’m sure we can look in to this and get it solved

Cheers

Sam

Update: After sticking to Dec 2021 version to avoid the chapter skip issue on mkvs with Atmos/DTS-X audio tracks until now, I thought let’s give the brand new July update a try hoping the issue was gone in the meantime as apparently lots of updates have been done incl. Kodi version uplift. Unfortunately, the issue is still there so I really regret the update as it will cost me some efforts to revert back. I still cannot believe that nobody else is facing chapter these skip issues.

I still need a sample clip.

You mention that you ripped them a long time ago. Is it possible that a new rip could work (on the theory that MakeMKV may have updated also since then)? Just ruling out another factor.