Hi there
I just noticed an annoying audio sync issue, which I didn’t see prior to the newest update (February 2024).
The video starts off correct, the with every second the audio is more and more delayed (audio is faster than video).
Verified on computer, video plays correctly.
Tried with and without audio passthrough, same issue. The video in question uses AAC codec.
Maybe related: Audio desyncing and random skips
Thanks for any hint how to fix this.
same here with my new vero5 while watching PVR/DVB-S2 Streams (with audio passthrought) via tvheadend backend. No problems with my old vero4k+. After a reboot, the audio sync Issues are gone for some hours?.. I don’t know the trigger…
Reboot doesn’t help in my case unfortunately.
Are you also watching Live TV?
I had the same problem right after the update with videos. A reboot seams to have fixed it. At least I have not noticed it since.
Are you also watching Live TV?
Nope. Only videos from video source (NAS).
I had this happen to me twice while my wife was watching some episodes.
Both times a reboot fixed it so I didn’t bother looking into it.
But since others are mentioning it, I will see if it happens again and if I can grab logs.
There’s no need for logs. I’m already working on it.
If it helps, here’s a comparison between two video files with roughly the same size and similar codecs. But one video works correctly on OSMC, the other one has the increasing audio desync issue.
Working video:
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 1 h 25 min
Bit rate : 5 447 kb/s
Width : 720 pixels
Height : 404 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.781
Stream size : 3.26 GiB
Title : Working.Video.Episode
Writing library : x264 core 157
Encoding settings : cabac=1 / ref=3 / deblock=1:-1:-1 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.15 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-3 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=19.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Default : Yes
Forced : No
Audio
ID : 2
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Codec ID : A_AAC-2
Duration : 1 h 25 min
Bit rate : 224 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 SPF)
Compression mode : Lossy
Stream size : 137 MiB (18%)
Title : Working.Video.Episode
Writing library : Lavc58.35.100 libfdk_aac
Language : English
Default : Yes
Forced : No
Video running into increasing delayed audio / sync issues:
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.1
Format settings : CABAC / 5 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 5 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 1 h 33 min
Bit rate : 709 kb/s
Width : 720 pixels
Height : 404 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.098
Stream size : 476 MiB (85%)
Writing library : x264 core 164 r3103 941cae6
Encoding settings : cabac=1 / ref=5 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=8 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=crf / mbtree=1 / crf=21.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Default : Yes
Forced : No
Color range : Limited
Matrix coefficients : BT.709
Audio
ID : 2
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Codec ID : A_AAC-2
Duration : 1 h 33 min
Bit rate : 123 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 SPF)
Compression mode : Lossy
Delay relative to video : 9 ms
Stream size : 82.3 MiB (15%)
Default : Yes
Forced : No
I noticed the 4 vs. 5 frames but I’m not sure if this would be a trigger. I’m not deep enough into video codecs to immediately spot the potential trouble-maker.
The problem here is the frame rate of 25 fps and the “progressive” scan type. I bet that “progressive” is wrong and the video is an interlaced one. That causes some (let’s say) irritations in Kodi. And in the end it can lead to that sync issue that you experience.
I’m aware of that (and other) reasons that can trigger sync issues. The problem here is to find the fixes that don’t break other things as a side effect.
For instance, I’m currently playing around with some fixes that work perfectly from the beginning of a movie till the end, where every frame is exactly in sync with audio. But (and there needs to be a but) Kodi now tends to drop frames. Sometimes I get only 2 or 3 dropped frames within 2 hours, and then suddenly if I play the same video again, I could get 30 dropped frames within the first 10 minutes.
So, yes, it’s an intersting journey … 
.
My wife was watching the UK original The Office, so that makes sense.
Hi,
this issue also occurs in my raspberry pi after the latest update. It’s unbearable to watch streams at the Moment. Is there a quickfix vor should Idowngrade for the moment?
Best,
Henning
Great to hear of the problems and your thoughts of how to overcome them, thanks for your efforts👍
This topic concerns playback problems on Vero V, so won’t be related.
@tanio99 @sam_nazarko any idea when a bug fix is ready to test? let me know, i’ll happily be a guinea pig for a fix.
right now the Vero V is not in use anymore, around 90% of all streams are not working. Either because of audio desync or heavy stuttering (on mostly older videos).
It’ll take a while. I’m working on that topic for half a year now and it’s driving me crazy. Sometimes (as mentioned above) everything’s fine, I can watch movies without any issue, and then I get a lot of frame drops although I haven’t changed anything. I suppose it’s Linux scheduler related and completely random.
It’s also hard to reproduce. One test always takes around 45 minutes until I can say if it really works or not. So unfortunately, it seems you have to be patient.
Although this problem has indeed persisted for a considerable period, it has become truly intolerable to watch Live TV from my end since the latest update. Prior to the update, it occurred sporadically, as you (@tanio99) mentioned, and although it was a little annoyance, it was manageble. However, since the February 2024 update, the issue starts almost instantly on live TV, and the delay is no longer just 0.5 seconds as it was before, but the audio is out of sync by approximately 2-3 seconds. Restarts resolve it, but the delay starts in a few mins.
February 2024 update on Vero V with DVB-S2 on Astra 28.2E I can’t reproduce this problem with BBC1 London.
But I’m only leaving it on for an hour or so and coming back to it. If I need to try for longer, let me know. Are you watching Live TV streams with a DD track by any chance?
To be fair, there were TVH updates as well 1 or two recently, so I am not 100% sure OSMC is to blame, but saw this thread and thought to add my case as well.
It’s also a DVB-S2, but on Thor on my side. No, it’s not DD track on the channel we use to watch.
short Update: From my opinion, the audio sync issue while playing PVR records (DVB-S2 from tvheadend) iss much more bad as directly from live stream.