Out of sync audio


#1

Hi ,  i have a WD HD TV ( 2nd gen )  ( firmware   1.01.75 )

The audio is out of sync on my mp4 ( h264/aac ) files .:cry:

My avi files play ok

Any ideas ?

Thanks …


#2

Same happens to me! Really really sad, since I have a couple of hundred files in that format!.. Usually I just press rewind and play sequentially, but that solves the problem for 1 or 2 minutes only.

That would be a really good improvement to be made in the next firmware if possible.

Thanks.


#3

Actually, I should include x264 files too… same problem.


#4

I have 1st gen current firmware and there it also seems to be a problem with the mkv/x264/acc and mkv/x264/ac3 as well - it seems to have somthing to do with the video because i did re encode my files with from ac3 - acc because i thought that was the problem. But it still happened… I had to re encode again as a mp4/x.264/acc this worked for me… i used handbrake… it must be a setting in the video that is causeing this…


#5

Ok so after some advaced testing… I have come to the conclustion that it is the fps that is the problem… it cant play mkv files at 29 - 30 fps… it needs to be at around 24-27 fps… however this doesnt solve the problem for mp4’s i have a mp4 at 29 fps that works :frowning:

MEDIA INFO OUTPUT FROM OUT OF SYNC FILE:

Format                           : Matroska
File size                        : 11.7 MiB
Duration                         : 1mn 11s
Overall bit rate                 : 1 369 Kbps
Writing application              : HandBrake 0.9.4

Video
ID                               : 1
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : Main@L3.0
Format settings, CABAC           : Yes
Format settings, ReFrames        : 2 frames
Muxing mode                      : Container profile=Unknown@3.0
Codec ID                         : V_MPEG4/ISO/AVC
Duration                         : 1mn 11s
Width                            : 720 pixels
Height                           : 480 pixels
Display aspect ratio             : 4:3
Frame rate                       : 29.970 fps
Standard                         : NTSC
Resolution                       : 8 bits
Colorimetry                      : 4:2:0
Scan type                        : Progressive
Writing library                  : x264 core 79
Encoding settings                : cabac=1 / ref=2 / deblock=1:0:0 / analyse=0x1:0x111 / me=hex / subme=6 / psy=1 / psy_rd=1.0:0.0 / mixed_ref=0 / me_range=16 / chroma_me=1 / trellis=0 / 8x8dct=0 / cqm=0 / deadzone=21,11 / chroma_qp_offset=-2 / threads=6 / nr=0 / decimate=1 / mbaff=0 / constrained_intra=0 / bframes=2 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=1 / wpredb=0 / wpredp=2 / keyint=300 / keyint_min=30 / scenecut=40 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=20.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Color primaries                  : BT.601-6 525, BT.1358 525, BT.1700 NTSC, SMPTE 170M
Transfer characteristics         : BT.709-5, BT.1361
Matrix coefficients              : BT.601-6 525, BT.1358 525, BT.1700 NTSC, SMPTE 170M

Audio
ID                               : 2
Format                           : AAC
Format/Info                      : Advanced Audio Codec
Format version                   : Version 4
Format profile                   : LC
Format settings, SBR             : No
Codec ID                         : A_AAC
Duration                         : 1mn 11s
Channel(s)                       : 2 channels
Channel positions                : L R
Sampling rate                    : 48.0 KHz
Language                         : English

MEDIA INFO OUTPUT FROM WORKING FILE:

Format                           : Matroska
File size                        : 11.0 MiB
Duration                         : 1mn 11s
Overall bit rate                 : 1 284 Kbps
Writing application              : HandBrake 0.9.4

Video
ID                               : 1
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : Main@L3.0
Format settings, CABAC           : Yes
Format settings, ReFrames        : 2 frames
Muxing mode                      : Container profile=Unknown@3.0
Codec ID                         : V_MPEG4/ISO/AVC
Duration                         : 1mn 12s
Width                            : 720 pixels
Height                           : 480 pixels
Display aspect ratio             : 4:3
Frame rate                       : 26.147 fps
Standard                         : NTSC
Resolution                       : 8 bits
Colorimetry                      : 4:2:0
Scan type                        : Progressive
Writing library                  : x264 core 79
Encoding settings                : cabac=1 / ref=2 / deblock=1:0:0 / analyse=0x1:0x111 / me=hex / subme=6 / psy=1 / psy_rd=1.0:0.0 / mixed_ref=0 / me_range=16 / chroma_me=1 / trellis=0 / 8x8dct=0 / cqm=0 / deadzone=21,11 / chroma_qp_offset=-2 / threads=6 / nr=0 / decimate=1 / mbaff=0 / constrained_intra=0 / bframes=2 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=1 / wpredb=0 / wpredp=2 / keyint=270 / keyint_min=27 / scenecut=40 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=20.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
Color primaries                  : BT.601-6 525, BT.1358 525, BT.1700 NTSC, SMPTE 170M
Transfer characteristics         : BT.709-5, BT.1361
Matrix coefficients              : BT.601-6 525, BT.1358 525, BT.1700 NTSC, SMPTE 170M

Audio
ID                               : 2
Format                           : AAC
Format/Info                      : Advanced Audio Codec
Format version                   : Version 4
Format profile                   : LC
Format settings, SBR             : No
Codec ID                         : A_AAC
Duration                         : 1mn 11s
Channel(s)                       : 2 channels
Channel positions                : L R
Sampling rate                    : 48.0 KHz
Language                         : English


As you can tell the only thing that is different is the frame rate

MEDIA INFO OUTPUT FROM WORKING MP4 FILE:


Format                           : MPEG-4
Format profile                   : Base Media / Version 2
Codec ID                         : mp42
File size                        : 174 MiB
Duration                         : 24mn 1s
Overall bit rate                 : 1 010 Kbps
Encoded date                     : UTC 2010-01-04 18:34:58
Tagged date                      : UTC 2010-01-04 18:41:28
Writing application              : HandBrake 0.9.4 2009112300

Video
ID                               : 1
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format profile                   : Main@L3.0
Format settings, CABAC           : Yes
Format settings, ReFrames        : 2 frames
Codec ID                         : avc1
Codec ID/Info                    : Advanced Video Coding
Duration                         : 24mn 0s
Bit rate mode                    : Variable
Bit rate                         : 683 Kbps
Width                            : 720 pixels
Height                           : 480 pixels
Display aspect ratio             : 4:3
Frame rate mode                  : Variable
Frame rate                       : 25.839 fps
Minimum frame rate               : 15.152 fps
Maximum frame rate               : 30.303 fps
Original frame rate              : 29.970 fps
Standard                         : NTSC
Resolution                       : 8 bits
Colorimetry                      : 4:2:0
Scan type                        : Progressive
Bits/(Pixel*Frame)               : 0.077
Stream size                      : 117 MiB (68%)
Writing library                  : x264 core 79


#6

I just came to these forums after experiencing this issue with an .mp4 file myself. It played, the sound was fine, but the framerate was just slightly off. My girlfriend and I even went and checked the framerate on my laptop to check to see if that’s what the director intended and yeah…NO. Every other file type seems to be playing just fine it’s just some MP4s.

I’m going to try converting to another file type tonight to see if that fixes it. In the mean time, can we get some mp4 support please?


#7

Hi Guys,

I  would like to add my discoveries on this issue. I have 250 DVD ISO’s of which I’m about 25% through converting to MKV with Handbrake.

These are exclusively PAL sources so the Framerate is 25fps which rules out the Frame rate idea on my files. What I have discovered is as follows.

ALL DTS Passthrough Play fine and perfectly in sync 100% of the time.

Any AC3 passthrough 5.1 discreet or 2 channel ProLogic start off in sync and within 10-15 minutes are at least half a second out. Stopping and resuming fixes the issue for while but it comes back again.

Some people have stated that switching the Audio Output from Digital (I’m using a HDMI AV AMP) to Stereo fixes this issue it doesn’t.

It has also been claimed that using the Same as Source setting for Framerate in Handbrake (This sets the Variable Frame Rate flag in the file) is the cause and switching to a  CFR Fixes the issue it doesn’t it only lessens the issue the Audio still drifts just by a smaller amount which is less noticable.

Given the VFR and DTS works fine but CFR or VFR with AC3 shows the issue in varying amounts there must be a Firmware bug in the sync of AC3 streams.

Sorry I haven’t tested AAC as i don’t re-encode my Audio as my conversions get played lound on Home Cinema kit exclusively and not on any portables.