Just want to add my name to the list of users experiencing audio sync issues.
Apple TV / iOS
For me it is a gradual build up in the sync issue. For example, after 30 minutes I start to notice some audio sync issues, minute and not distracting, after an hour there is about a half second delay, watchable but barely, after an hour and a half I have to turn it off because it’s all I can focus on.
In the past, when this has happened, I simply stopped the video and restarted from that point, except, with this newest update, the video crashes if I ever leave it, rewind or fast forward for any reason. Pausing is okay though. So if I want to watch any video I have to do it in one go.
Good thing I keep AirVideo around just in case.
Same here. Happens on all clients including PlexWeb. I have a 2013 Mac mini i7 16gigs RAM and 256SSD, with enough upload for remote HD content. Doesn’t matter how, whether iOS, AppleTV2 w/ jailbreak and/or via Airplay, or simply on PlexWeb, it will often be out of sync. I’ve noticed this on AVI, MP4, and MKV. Closing the iOS app and starting from beginning will resync but only for a few minutes.
this is really annoying, before all other features are released, this should be fixed. There’s no point to any of it if you can’t watch it.
Count me as another with audio sync issues. Only seems to happen on AVI’s. It’s fine if I play it on iOS but on the Mac Client 0.9.5.4 it will be out of sync about 300ms behind so its fixable but the wife acceptance factor is getting lower. The AVI’s play fine in Quicktime.
This is on a brand new 2012 i7 Mac Mini, 16GB RAM running 10.8.2
This is still my biggest complaint for Plex/Mac.
Can also confirm AVI files are played out of sync on the Plex Mac client app (about 200ms on my machine). All other formats seem ok. The Web player does play AVI files just fine, as does any other player (QT,VLC,etc).
I'm using iFlicks to convert most of the AVIs to MOVs, which solves the problem (some AVIs unfortunately can't be converted and actually need a re-encode).
My machine is a Hackintosh running OS X 10.7.5 with Intel i7 920 @ 2.8GHz (quad core with HT) and ATI 5850 1GB graphics card. Interestingly, the client app takes some 30 seconds to load (it's on an SSD no less). My partner's Macbook Air loads the app in ~0.2 seconds. Go figure...
I have some input, maybe not helpful but I am just curious. I have the same issue on my main TV but not on my laptop. The i7-2600k hackintosh is connected to my Onkyo receiver then it is going out to the TV. The way my setup is I can't test a direct connection but I'd be curious to know if anyone else is connected in this way. The problem files are the same for me, older SD files that are avi, about 300ms offset They play fine on other applications and I don't seem to have any problems when playing the same files from Plex Media Server to the appleTV or Roku3. I suppose they are being transcoded which I assume is fixing the issue. On a good note (at least for me) I have not noticed any HD files being affected. Other people try to force transcoding though and see if that helps. It shouldn't be a noticeable difference in quality anyway since its SD files that are affected. Good Luck.
Both my laptop and hackintosh are running the same versions of Plex client 9.5.4. My laptop is a macbook air. I think someone with a windows client should chime in too since it sounds like a bunch of Mac users from what I gathered.
Count me in too. Brand new low-end Mac Mini. Doing HDMI straight from the Mini, via my receiver, to my TV.
At first, I noticed a desync of about .25ms in certain files. After tinkering, I seems to have pinpointed the problem to the option "Adjust display refresh rate to match video". If I enable that, I get desync in some files. If I don't, audio is fine and in sync but I get the usual problem with jittery playback, the very issue that the beforementioned option was created for.
I also can't combine the display refresh rate adjust option with "digital" or "hdmi" audio output. I get about 1-2 FPS and no sound.
Using the analog audio option isn't really a problem since I seem to get working surround regardless. The Mac Mini just seems to send the same 5-channel audio regardless if there's anything to fill the channels with or not. If I enable HDMI or Digital audio in Plex, the receiver display lights up with the correct number of channels.
I'm confused.
Reading the documentation of another application which handles video files, I came across a technical explanation on one severe audio sync issue with mp4/mov files and the plex video player.
The developer of the software explains, that some players are only partially mp4-ISO compliant (including plex and mplayer), while others are fully compliant (VLC, QuickTime). The players with sync issues do not fully read the atom information of the file, especially skipping the edit list entries of the track atom and they only rely on the offset chunk tables. If a movie has been cut aside it´s keyframes, those players will be out of sync by the first cut position.
I easily replicated the problem with a mov-file that has been cut by frame (not key-frame) using the QT framework. It lost sync at the expected moment. VLC keeps all sync.
workaround: The developer of the other software (it is used for cutting recorded TV shows) suggests converting affected mp4/mov files to mkv using the command line tool mkvmerge, as mkvmerge reads all atom information when remuxing.
The plex developers should feel encouraged to make their player fully mpeg4 compliant. Sometimes things are easier, if you just do them right. Alternatively there could be an option which player to use. It is very sad, that plex serves its main purpose so poorly.
Documentation can be found here:
http://www.mp4ra.org/atoms.html
http://wiki.multimedia.cx/index.php?title=QuickTime_container#elst
The elst atom contains the edit list. The edit list contains information about the times and durations that pieces of a media track are to be presented during playback. There are many Quicktime file decoders that choose to ignore this atom. This is not a good idea. The edit list atom must be taken into account to guarantee proper A/V sync on certain files.
and my source, "superotr decoder" (German language):
Any news on this? I am still having this problem and while I like Plex, I am looking to other alternatives by now.
Hey Plex, it's 2015 and I'm reading a thread that's a year and a half old and I'm having the same problems as all the others. Mainly on the web interface using Chrome. Has this issue not been resolved?
Audio sync falls out of time gradually and becomes unbearable. I mainly use PlexConnect on ATV2 and the web interface on my 2013 MacMini. It seems to happen more frequently with HD videos over 3 or 4GB in size, but it could be something else too? It seems ridiculous that mp4 or mov or mkv or m4v would have these issues. Is there a format that one can guarantee helps this sync issue?
Thanks.
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Update:
So far my issue has been resolved by using Firefox instead of Chrome for the web player.
I'm having the same issue. Doesn't matter which Plex player I use: Roku, PlexConnect, etc. All out of sync. VLC has no issue playing the same files. :(
I'd be glad to upload a sample if it'll help the devs.
Hey guys! Would love to help you out, but the quality of the bug reports in here are shifting fram bad to good. And this is a super old thread and many of you guys are talking about different things. We will never get to the bottom of this thing without some structure. So if you guys are willing to put some structure in place, I am happy to be of assistance :)
A few of you are talking about Direct Play, and some are talking about transcoding. Some are having issues in only some clients and so on.
So lets start with some rules. From now on, ever report has to be super specific. Which client are you referring to? Which version? Which OS do you have PMS on? Which client OS are you on? Does it happen to only some files? All files? What is the commonality between the files that is not working?
Lets do something like this. Fill in and post this:
Client:
Client Version:
Client OS:
Direct Play, Transcoding or Both:
PMS version:
PMS OS:
Filetypes/Codecs that works:
Filetypes/Codes that shows the symptoms:
Approximately how much desync does it get:
Desync happens directly on movie start Y/N:
Link to sample file (here is how, and make sure to test the sample file before uploading, so you are sure that the sample shows the same issue as the original):
Desync happens only after I jump in time Y/N:
Other clients that you have tried as well, and if they show the same issue or not:
Free text explanation:
I have been searching all over for an answer to my random audio issues from mac to tv (via roku) and haven’t found a concrete answer yet…
BUT, I will say something no one has mentioned yet (so far in my skimming) is that this issue ONLY happens for me when the audio codec is AAC!
AC3=no issues.
Any one else trial and error this? If we all do… maybe they will fix it? (ha…ha…)
Once I noted that I made a point of only downloading AC3 files. Of course, sometimes you have no other option and for this I can say the only way to watch it is to exit to the main plex menu and resume playing. It will fix it for 3-5 mins at least and then you can do it again. Super annoying, but so far the only work around?
Any other ideas?
I’m also having audio sync issues with some of my avis. Like the files will start sync’d but then lose it 10 minutes or so in. 
You’re responding to a thread that is over three years old since the last post and was first created nearly 7 years ago. Nothing in this thread applies to anything today 
Can you please:
- Start a new thread
- Tag it
server-mac(orserver-wind0wsas appropriate) - Be sure to include the Server version number
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