62 replies to this topic

[fhqwhgads]

Hello,

Thanks for the awesome software, I am already a huge fan of Plex. But I have a major problem that I hope someone can shed some light on. I have searched the forum for related issues, but so far have not found anything directly related to this particular issue.

Apologies in advance for the long post. I do tech support for an audio interface company as my day job, so I am trying to anticipate your questions and detail my troubleshooting process so far.

The problem:

I have quite a few DVD rips that are not playing properly in Plex. These are MKV rips from commercial DVDs. The tool used for ripping these is MakeMKV. This software just pulls the untouched MPEG2 video off the DVD and wraps it in an MKV container. When ripping I deselected the subtitles and extra audio tracks, so only the feature video with default audio remains.

The audio lags behind the video. At start, the audio and video are perfectly in sync, but after a short period the lip sync is definitely off. The time it takes seems to vary a bit from file to file, but between 5 and 15 minutes in it is too annoying to continue. It seems to get progressively worse as the file plays. In order to resync, I have to stop and resume playback (pause/play does not resync).

I have some MP4 videos ripped from DVD with HandBrake that do not exhibit any sync problems. The same file causing problems in Plex plays perfectly in MPlayer OSX Extended* on the same hardware. The same file also plays almost perfectly on my WD TV media player**, so I really think this may be a combination of a Plex issue and a file problem. Interestingly, I also have some shorter (45 min) TV episodes ripped from DVD (same method used) that seem to stay in sync throughout.

* In order to get perfect playback in MPlayer OSX Extended, I have to set "Screenshot location" to "disabled". There is some issue with filters and MPEG2 video that causes video tearing with the default options. VLC plays fine as well, but skipping in the timeline crashes current VLC builds.

** "Almost perfectly" here means the audio sync is perfect, but there were a couple unusual glitches during playback on the WD TV hardware.

My hardware is a stock new Mac Mini 2.26GHz w/ 2GB RAM, file playback from a WD hard drive (USB2, HFS+ Journaled). Kanex Mini DisplayPort to HDMI adapter, HDMI to TV input. The TV is a Panasonic plasma (TC-P50G10). The Mac Mini display preferences are 1080p/60Hz.

I tested both decoding at the receiver (mini toslink to toslink) and using the analog out of the Mac Mini. No difference.

Any ideas for troubleshooting, fixes, or confirmation are appreciated!

# Is it reproducible?
# Can you document the steps to reproduce it so that happens every time?

Yes. As far as I can tell, any commercial DVD feature film ripped to MKV with MakeMKV will exhibit the problem. It seems that some rips are playing fine, but others exhibit problems (ripped identically). I'm checking files as quickly as I can, but so far the worst ones are "Year One" and "Drag Me To Hell".

# Does it still happen after deleting /Users/USERNAME/Library/Application Support/XBMC ?

Yes, even after a complete removal of all Plex files and reinstallation.

# Does it happen on any other machines you have around the house/office?

Yes, also on my MBP 4,1 with Plex v0.8.3 and OS X 10.6.2.

EDIT: Here is a clean log file, from program start to program quit after the movie became unwatchable. I don't see any relevant messages here though.

http://pastie.org/699630

Regards,
Jeff

[fhqwhgads]

Quick update. I have been doing more testing and research, and it seems that this is a known bug in all XBMC variants, which I guess means some problem with the FFMPEG version. This is odd since the same file plays well in MPlayer OSX Extended.

The latest XBMC release (9.11 alpha 2) does not play these files well, lots of video glitching/skipping.

Some relevant threads are linked below.

http://forum.boxee.tv/showthread.php?t=12432&highlight=makemkv
http://xbmc.org/forum/showthread.php?t=61140&highlight=makemkv
http://www.makemkv.com/forum2/viewtopic.php?f=1&t=606

Does anyone have a bright idea? I have seen people recommend remuxing with mkvtoolnix (tried it, no change) or remuxing to TS (no tools for OS X as far as I can see).

I would hate to run all these files through HandBrake, there is a noticeable quality loss when transcoding this compressed MPEG2 video.

[Tommye1078]

I'm have the same problems with some of my blurays ripped via makeMKV. Any ideas on whats going on.

[eriko]

I'm have the same problems with some of my blurays ripped via makeMKV. Any ideas on whats going on.

I'm having the exact same issues. I'm encoding with HandBrakeCLI, and most (not all) of my movies have horrible sync. Latest Plex, Snow Leopard, 720p.

Has anyone found a solution?

[Wildcat_1]

I'm having the exact same issues. I'm encoding with HandBrakeCLI, and most (not all) of my movies have horrible sync. Latest Plex, Snow Leopard, 720p.

Has anyone found a solution?

I am running handbrake 0.94 and just ripped my entire 24 collection to MKV and am seeing the same issues (audio lag) in plex on these. Anyone have a solution, is it truly Plex playback or the MKV files being ripped by Handbrake ? When I play in VLC the files looks great

Thanks

WC

[shagelific]

I am running handbrake 0.94 and just ripped my entire 24 collection to MKV and am seeing the same issues (audio lag) in plex on these. Anyone have a solution, is it truly Plex playback or the MKV files being ripped by Handbrake ? When I play in VLC the files looks great

Thanks

WC

I am having the same trouble. mkv's ripped with handbrake and the audio goes out of sync. vlc plays them perfectly. I love plex, but I really need to find a fix for this.

[yogibeer]

I'm also having audio sync problems with mkv's encoded using HandBrake. I have two videos both play fine in VLC with no audio sync issues. However the one I encoded using HandBrakeCLI goes out of sync when I watch it using Plex, the other one (from an undisclosed source) does not.

The real difference is the fact that the good one has AC3 as it's only audio track, while the bad one has both AAC and AC3 audio streams. Plex is playing the AAC audio track when it goes out of sync. I'll try using the AC3 track instead and see if the same problem occurs.

EDIT: I tried playing the AC3 track and it still went out of sync.

Attached is the mkvinfo output for both the good and bad mkv.

Attached Files

•  bad.txt   3.22K   5 downloads
•  good.txt   1.27K   0 downloads

Edited by yogibeer, 13 March 2010 - 06:33 AM.

[justmeee]

I'm also having the same problem and I have the same setup (new mac mini and using makemkv). My guess that the problem lies somewhere in Plex. If we know that the actual file is ok, and it must be because when I chapter skip to later in the movie, the sync is perfect. It seems to only happen when I'm watching a movie and it's a good hour in or so. It's very annoying. So much so that I really don't want to watch any of my makemkv flies until someone can actually figure out why this is happening.

[elan]

Quick update. I have been doing more testing and research, and it seems that this is a known bug in all XBMC variants, which I guess means some problem with the FFMPEG version. This is odd since the same file plays well in MPlayer OSX Extended.

The latest XBMC release (9.11 alpha 2) does not play these files well, lots of video glitching/skipping.

Some relevant threads are linked below.

http://forum.boxee.tv/showthread.php?t=12432&highlight=makemkv
http://xbmc.org/forum/showthread.php?t=61140&highlight=makemkv
http://www.makemkv.com/forum2/viewtopic.php?f=1&t=606

Thanks so much for the investigation, it's much appreciated!

It seems likely that there would be an XBMC or Boxee-sourced fix for this in the not-to-distant future, at which point we could pull it into Plex without much trouble. Please feel free to contact me directly when/if this is the case.

[shagelific]

Thanks so much for the investigation, it's much appreciated!

It seems likely that there would be an XBMC or Boxee-sourced fix for this in the not-to-distant future, at which point we could pull it into Plex without much trouble. Please feel free to contact me directly when/if this is the case.

the last post in this thread seems to indicate that the problem was fixed in xmbc. i can't confirm though.

[elan]

the last post in this thread seems to indicate that the problem was fixed in xmbc. i can't confirm though.

Thanks very much. Cherry picked for the next version

[aquafunk]

The problem:

I have quite a few DVD rips that are not playing properly in Plex. These are MKV rips from commercial DVDs. The tool used for ripping these is MakeMKV. This software just pulls the untouched MPEG2 video off the DVD and wraps it in an MKV container. When ripping I deselected the subtitles and extra audio tracks, so only the feature video with default audio remains.

The audio lags behind the video. At start, the audio and video are perfectly in sync, but after a short period the lip sync is definitely off. The time it takes seems to vary a bit from file to file, but between 5 and 15 minutes in it is too annoying to continue. It seems to get progressively worse as the file plays. In order to resync, I have to stop and resume playback (pause/play does not resync).

I have some MP4 videos ripped from DVD with HandBrake that do not exhibit any sync problems. The same file causing problems in Plex plays perfectly in MPlayer OSX Extended* on the same hardware. The same file also plays almost perfectly on my WD TV media player**, so I really think this may be a combination of a Plex issue and a file problem. Interestingly, I also have some shorter (45 min) TV episodes ripped from DVD (same method used) that seem to stay in sync throughout.

I have the exact same issue with your exact steps. MakeMKV>Remove other audio tracks>remove specific subtitles>play in Plex, audio sync of doom>play in VLC, viola. Hope the fix is released officially soon!

[shindigg]

If this is still an issue for you, try this.

[hamachi]

Thanks very much. Cherry picked for the next version

has this fix been released? or will it be in ver. 9?

[TruBrew]

I am very much anticipating a fix, it will determine when I build a network server.

[TruBrew]

double post, I don't know how to delete it.

[chapindad]

I have this problem with some of my MKV files that I ripped with makemkv. I have not tried in vlc to see if it is just a plex problem. Is this a known problem that is being fixed in .9 plex? Is this just a known mkv problem? Should I go back to Ts_folders?

Thanks

[Buckets]

So can anyone confirm that this was fixed in Plex/Nine?

[motoko]

I'm experiencing this problem still with Plex 0.9

[aquafunk]

I'm experiencing this problem still with Plex 0.9

That sucks :[

Please, someone, anyone, fix this! :*[