Delayed sound playing one particular MKV

[Mr. Protocol]

I've got a series of MKV video files from the same source in which the sound is delayed by about 2.5 seconds. Changing the sound timing offset in the Audio submenu doesn't do a thing. These files all play correctly on the desktop in VLC, however. There's nothing odd about them that I can see: they're 1280x720 H.264 video, 48KHz stereo AAC audio. It's as if the encoding is so compressed that the box is running out of cycles or something.

Has anybody else seen something like this? I'm running the most recent update on the box.

[Prospero424]

This usually fixes odd syncing issues I occasionally see with mkv files:

Download and install the MKVToolnix package, then open MKVMerge GUI. Drag one of the problem mkvs to its input window at the top, select your output folder and file name at the bottom, and click "mux".

Let me know if this fixes it.

[Whopper]

Same here I have the movie Chloe.(2009).mkv which plays fine via VLC but has a horrible and unfixable 2 -3 seconds sound delay

[Mr. Protocol]

This usually fixes odd syncing issues I occasionally see with mkv files:

Download and install the MKVToolnix package, then open MKVMerge GUI. Drag one of the problem mkvs to its input window at the top, select your output folder and file name at the bottom, and click "mux".

Let me know if this fixes it.

I downloaded and installed the MKVToolnix package and did as you suggested. Unfortunately it had no effect whatsoever.

[Mr. Protocol]

This usually fixes odd syncing issues I occasionally see with mkv files:

Download and install the MKVToolnix package, then open MKVMerge GUI. Drag one of the problem mkvs to its input window at the top, select your output folder and file name at the bottom, and click "mux".

Let me know if this fixes it.

It didn't. Any other ideas?

Alternatively, anyone know if/how I should upload one of the offending files to Boxee for testing? Or, would it help if I contacted the group who generated the encoding and ask them what they used to do it, and with what parameters? I've already listed the overall parameters in the original post but that says nothing about interleaving, frame rate, etc.

[Prospero424]

You'll want to cut out a short sample (10-20 seconds) and post a download link to it here and/or in a Jira ticket related to the issue. A lot of people use Dropbox or something like Rapidshare to host their samples, but it's up to you.

Here's a quick guide to cutting out a short sample from a .mkv file.

[Iznogood]

1:
Download and install - MediaInfo - http://mediainfo.sourceforge.net/

2:
Right click your video file, open with mediainfo and view in text mode.


3:
Copy/paste the text into this thread.

[Mr. Protocol]

General
Unique ID : 248268456058955775390610760529806896076 (0xBAC6C3EFC079792E9005FAAB69B02BCC)
Complete name : /Volumes/Drobo-A/INCOMPLETE/Ao no Exorcist/[gg]_Ao_no_Exorcist_-_06_[26E1DD02].mkv
Format : Matroska
File size : 466 MiB
Duration : 24mn 34s
Overall bit rate : 2 648 Kbps
Encoded date : UTC 2011-05-22 15:06:06
Writing application : mkvmerge v4.4.0 ('Die Wiederkehr') built on Oct 31 2010 21:52:48
Writing library : libebml v1.0.0 + libmatroska v1.0.0
Cover : Yes / Yes / Yes / Yes / Yes

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings, CABAC : Yes
Format settings, ReFrames : 9 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 24mn 34s
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Variable
Frame rate : 23.976 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Title : Ao no Exorcist - 06
Writing library : x264 core 114 r1913 5fd3dce
Encoding settings : cabac=1 / ref=9 / deblock=1:0:0 / analyse=0x3:0x113 / me=umh / subme=10 / psy=1 / psy_rd=0.80:0.20 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=-3 / threads=12 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / constrained_intra=0 / bframes=5 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=300 / keyint_min=29 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=0 / crf=18.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / vbv_maxrate=50000 / vbv_bufsize=50000 / crf_max=0.0 / nal_hrd=none / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:0.80
Language : Japanese
Matrix coefficients : BT.709-5, BT.1361, IEC 61966-2-4 709, SMPTE RP177

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : A_AAC
Duration : 24mn 34s
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Compression mode : Lossy
Title : AAC 2.0
Language : Japanese

Text
ID : 3
Format : ASS
Codec ID : S_TEXT/ASS
Codec ID/Info : Advanced Sub Station Alpha
Compression mode : Lossless
Title : ass
Language : English

Menu
00:00:00.000 : en:Prologue
00:00:54.129 : en:Opening
00:02:23.969 : en:Main
00:22:19.829 : en:Ending
00:23:49.709 : enerchan's wet dreams
00:24:19.699 : en:Preview

[Mr. Protocol]

And here we have a clip from the offending video, duly extracted via Mkvtoolnix. It's about 75M in size, as suggested. It plays perfectly on the desktop in Quicktime 7 + Perian. On the Boxee Box, not only does the sound fall out of sync, but the video freezes from time to time.

http://dl.dropbox.com/u/31202131/%5B...281%29-002.mkv

[Prospero424]

Ah, that explains it. The Boxee Box often has trouble with anime movies that use variable frame rate. Anime shows in particular often use one frame rate for part of the show and another for the rest, and some encoders handle this by using a variable frame rate, which can cause problems with some players.

Anyway, Boxee's aware of the issue and trying to fix it. Here's the Jira bug tracker page where they were soliciting samples, including an FTP server that you can upload your sample to.