I’ve been using the android app “AV Sync”.
Interesting. I tried this app once with the Spears & Munsil audio sync test, but it didn’t work at all. It gave me offsets of 200-500 ms or something, which definitely was not the case.
Provided the markers for both video and audio have been set correctly, I’ve had no issues and it’s always matched what I am seeing.
I have narrowed down the problem to the setting to Settings>Player>Adjust Display Refresh Rate.
When this is on, I have audio sync issues for multiple file types, and it’s random. Sometimes okay, sometimes off. Often recurs when skipping forward and backward.
Turning this off solves the issue, but then Dolby Vision support doesn’t work. I only see a black screen.
The only workaround I have found is to disable Dolby Vision and turn off adjust refresh rate.
Hopefully there’s a fix for this soon.
Am using a RockTek G2 and CoreELEC 21.1.1 Omega NE.
I think that is a bit of a separate issue. I also have experienced the same blackouts when disabling match frame rate and using Dolby Vision, on the AM6b+ using NG.
I found minimum 2 more issues, like after boot first frame is missed and on first playback 9th frame is lost to. But it will need more intensive tests as multiple places must be fixed.
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It’s good to know you’ve managed to reproduce. 
Yep, I have this issue every time I boot up my device.
Repeated the test on 20241111 version with the additional audio/video component enabled.
20241111_kodi_video_and_av.log (3.2 MB)
Initially the audio delay was ~280ms, after a long time this changed to ~80ms. After a 10 seconds skip back the audio delay was ~320ms.
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Next nightly has again some changes about frame sync handling. But I am sure it’s not fixed yet.
It’s very hard to fix issues as the fix causes other work arounds like implemented at Kodi 17 as example to break everything…
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I’m still seeing variations in the a/v sync, but a general difference seems to be the offsets appear to have been generally shifted to be a less of a audio delay or even having the audio ahead. Never saw the audio ahead before.
If useful, I repeated the same test I did before with a log. Initially the audio was very close to spot on / very slightly late, after a while it settled to the ahead being ~3 or 4 frames ahead. After a 10 seconds skip back the audio delay was ~ 1 or 2 frames ahead.
20241115_kodi.log (3.2 MB)
Yes, I think this is because on first start it start at 0.0ms.
But the first frame take like 350ms to be displayed on screen.
So kodi try now to fix this by skip all frames to match up with the like 350ms again. And the audio sync is done before I guess.
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I have here very experimental devel for some sync tests:
It’s not finished yet, just to see if it’s going to correct direction…
It’s only now for Amlogic-ng.
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Are logs still valuable to you if I cant tell how far off the audio delay is?
Appears to be a regression to me, audio offset of over +400ms. Can’t really provide much more precise info than that though as the video playback is quite jerky and lots of frames weren’t displaying.
20241116130232_kodi.log (5.1 MB)
Yes, the jerky playback is because it’s a devel build.
The problem with the video/audio sync files is I don’t know if the beep is with correct frames.
They are in sync with frame 0.
But maybe the beep is like 24 frames to late/early.
Maybe this test image works better now, please have a test.
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Definitely better than the previous build.
For a eac3 track I’m consistently getting audio ~4 frames late on initial playback. changes to ~7 frames late after a seek. Need another log?
What sample? How to check?
File used was: Audio sync/Audio_Video_Sync_23.976_TEST TrueHD DTS-HD DDP DD PCM.mkv from 23.9976 link from Kodi Audio Out of Sync playing file or after seeking - #90 by R3S3T_9999
I had selected the DD+ track from that file on a previous playback to prevent potential issues that could come in by changing audio track while video was playing.
I did it both by eye and by measuring with phone app, both getting same results.