Lip-Sync error not a TV problem - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 13 Old 07-12-2010, 08:05 PM - Thread Starter
Senior Member
 
davenport47's Avatar
 
Join Date: May 2009
Posts: 447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Maybe I should put a question mark at the end of the thread title, but here is my observation (edited from the Vizio E420VL, etc. thread). I think it will be of general interest to all those who've complained about lip-sync trouble.

To wit:

While I've been waiting for our local Costco to get the Vizio E420VL, I've been watching a tiny little 13" Toshiba CRT TV for information viewing, etc.

The lip-sync problem still exists on some programming with that little Toshiba CRT. So it HAS to be coming either from the Comcast DVR box or from the source itself. Can't blame the Blu-Ray player which is temporarily unhooked. Can't blame the TV, which isn't even HD.

This means that manufacturers such as Sony and Samsung are, in a sense, passing the buck on this issue legitimately. IOW, how can the video processing of a 13" CRT be slower than the audio? Yet this idea---i.e., that HD video takes a few milliseconds longer to process than the audio---is offered as the cause of lip-sync error. Now, perhaps this is still true, but it's not the TV that's doing it!

What to do for those of us without a high-end AVR with lip-sync adjustment, and who use an ordinary stereo system or the TVs own loudspeakers? It appears that Vizio is the only choice until other manufacturers start giving us a lip-sync adjustment in the user menu. (Is it a patented Vizio thing that can't be used by others?)

The various threads lamenting this problem ought to realize that the TV isn't to blame.

But does it matter? Without an adjustment, the problem is still there, whatever the source. I've seen the lip-sync problem on several HD TVs with both broadcasts and DVDs. This is now an even bigger mystery if one can't blame a TV's video processing lag.

Comments?
davenport47 is offline  
Sponsored Links
Advertisement
 
post #2 of 13 Old 07-12-2010, 08:32 PM
Member
 
zforgetaboutit's Avatar
 
Join Date: Oct 2002
Location: Toronto
Posts: 168
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by davenport47 View Post

...

The lip-sync problem still exists on some programming with that little Toshiba CRT. ...

Comments?

Maybe the little Tosh has a correspondingly slower CPU that also can't handle the source material.
zforgetaboutit is offline  
post #3 of 13 Old 07-12-2010, 08:36 PM
AVS Special Member
 
shaddix's Avatar
 
Join Date: Mar 2006
Posts: 1,436
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
that thing has no cpu lol ^_^
shaddix is offline  
post #4 of 13 Old 07-13-2010, 09:22 PM - Thread Starter
Senior Member
 
davenport47's Avatar
 
Join Date: May 2009
Posts: 447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by zforgetaboutit View Post

Maybe the little Tosh has a correspondingly slower CPU that also can't handle the source material.

Shaddix is correct. No CPU.

Given the large number of posts on this bothersome lip-sync issue, one would think the cause of it would at least be known. Also that manufacturers other than Vizio would recognize a need for a fix, or at least a way for the purchaser to sync up the sound when necessary. If the higher-end Blu-Ray players and AVRs have an adjustment, why not the TVs? This is a cop out on the part of Sony, Samsung, LG, Toshiba, et. al. They seem to be betting on the notion that the majority of viewers just won't care.
davenport47 is offline  
post #5 of 13 Old 07-19-2010, 07:40 AM
Member
 
Joker_Da_Man's Avatar
 
Join Date: Mar 2010
Posts: 19
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I have confirmed using multiple tests beyond any doubt that my 55LH40 LG TV produces audio lag resulting in a lip sync problem. May I present:

1. Using my Xbox 360 hooked straight to TV via HDMI, I can approximate 70ms (170ms if Dolby Digital is enabled) audio lag using the Guitar Hero lag calibration screen. Due to the fact that this relies on me accurately strumming along with a beat, there is some margin of error--maybe 30ms?

2. Using a PS3 hooked straight to TV via HDMI, approximately the same audio lag numbers are observed. Also, for the PS3 I had a guitar with light and sound sensors which the game uses to calibrate itself (there is a screen which flashes between black and white, and it emits a series of clicks on the audio). This is sure to be more accurate than me strumming, and the numbers were similar to what I list above for the Xbox 360.

3. I bought a receiver which can decode HDMI audio. I connected my Xbox 360 to the receiver, and the receiver to the TV (all HDMI). Both TV and receiver speakers will play the sounds at the same time, but I can hear a definite delay on the TV speakers.

4. Even if you were to say that the Guitar Hero or Rockband games were to blame, I can tell the difference in Halo 3. The gun sounds are noticeably delayed when using the TV speakers.

5. An Xbox 360 connected to my dad's 2006 plasma TV showed no audio lag in Guitar Hero via HDMI. It would not take Dolby Digital over HDMI, but still showed no lag with stereo audio whereas my TV shows ~70ms audio lag. Even if 70ms seems small and may not be very accurate using calibration screens by hand, the gameplay difference is quite noticeable. I have difficulty playing well (non-calibrated in-game) with my TV's speakers but I had no such problem playing on his TV.

So, I doubt this is the bigger mystery that davenport47 implies it might be, especially on LG TVs. My current thought is that this has to do with the HDMI 1.3 spec's inclusion of functionality for the TV to specify how much audio lag is needed to match the video processing delay which the TV has.
Joker_Da_Man is offline  
post #6 of 13 Old 07-19-2010, 08:18 AM
Member
 
Joker_Da_Man's Avatar
 
Join Date: Mar 2010
Posts: 19
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
After having just read the relevant portions of the HDMI 1.3a spec (this is the version which introduced auto-lip-sync capability) I can see where the non-Dolby-Digital ~70ms of lag is coming from. Basically the TV can provide a value to the Xbox 360 (assuming Xbox 360 supports HDMI 1.3a, which I think it does) saying "I have 70ms of video lag*, please delay the audio by 70ms." So now the audio and video should match each other. However, the audio is then lagging my actions in the video game, which makes the game feel broken.

So this auto-lip-sync feature is helpful for movies but absolutely harmful for gamers. When I am playing Guitar Hero or Halo, I need to hear the audio as soon as possible, not when the video finally gets around to rendering.

As for ~170ms lag with Dolby Digital...I guess the TV just sucks at that. I wonder if anyone who has had their LG "fixed" with firmware is still actually getting DD to the TV, or if the fixes just involved disabling DD somehow?

*I don't think I observed video lag values as high as 70ms on my TV (I keep it in Game Mode), but it seems possible that LG just took a high-ish value so that audio and video match when people turn on all the 24p/120Hz/motion-smoothing features. In fact, the spec even suggests that when there is a lag difference between two video modes, to set an audio lag which trends closer to the higher video lag as audio leading video is more perceptible than video leading audio.
Joker_Da_Man is offline  
post #7 of 13 Old 07-20-2010, 01:17 PM
AVS Special Member
 
Steve S's Avatar
 
Join Date: Mar 2001
Location: Fresno CA
Posts: 5,356
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 46
Gaming aside and in response to the OP, poor audio synch was very common on HD cable, sat, and OTA signals in the early 2000s, wouldn't surprise me if it's still a problem on some channels or providers. I'm currently OTA only and don't experience it very often, never have a problem with other HD sources like BD or HD-DVD. In the bad old days it was much worse and intermittent, even if one stayed on a single channel, so I never bothered to use the adjustable delay on my receiver.

Steve S.
Steve S is offline  
post #8 of 13 Old 07-20-2010, 08:47 PM - Thread Starter
Senior Member
 
davenport47's Avatar
 
Join Date: May 2009
Posts: 447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Joker says: <<So, I doubt this is the bigger mystery that davenport47 implies it might be, especially on LG TVs. My current thought is that this has to do with the HDMI 1.3 spec's inclusion of functionality for the TV to specify how much audio lag is needed to match the video processing delay which the TV has.>>

Steve S says: <<. . . poor audio synch was very common on HD cable, sat, and OTA signals in the early 2000s, wouldn't surprise me if it's still a problem on some channels or providers.>>

It's becoming clear that lip-sync issues are a complex matter. Joker's problem doesn't apply to my observation about the little Tosh CRT. Yet Steve's does.

Allow me another example: When I had a 47" Samsung (eventually returned for flashlighting), I was watching a standard DVD of an old B&W movie, *Sink the Bismarck*, via a Panasonic Blu-Ray player. The sound was out of sync for about the first 15 minutes of the movie, and then corrected itself! How this can be I have no idea, but I experienced this twice using the Samsung. Other movies have been consistent (i.e., consistently out of sync or consistently in sync).

Anyone have an explanation for how a DVD can start off being slightly out of sync, then get into sync after a few minutes?
davenport47 is offline  
post #9 of 13 Old 07-20-2010, 08:53 PM
Newbie
 
john5757's Avatar
 
Join Date: Jul 2010
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I noticed that with my Pany DVD recorder/player the DVD Close Encounters of the Third Kind had three Dolby setups in the menus. One was Dolby surround, Dolby Digital and the last is DTS. I found that each has its own delay and the Dolby digital audio was way off of sync, quite bad. Lip-sync does help me to visually add to the sound since I was born with a hearing loss.
john5757 is offline  
post #10 of 13 Old 07-21-2010, 06:22 AM
Member
 
Joker_Da_Man's Avatar
 
Join Date: Mar 2010
Posts: 19
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by davenport47 View Post

Anyone have an explanation for how a DVD can start off being slightly out of sync, then get into sync after a few minutes?

Since you said it was an older B&W movie and that is the only DVD you have that problem with, I would guess it was a mastering problem.

Now why you have some movies out of sync and some in sync...could that be because they have different soundtrack encodings? (Dolby Digital vs whatever else)
Joker_Da_Man is offline  
post #11 of 13 Old 07-21-2010, 06:31 AM
AVS Special Member
 
serialmike's Avatar
 
Join Date: Jan 2005
Location: Florida
Posts: 2,745
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 17
If the hdmi1.3 spec is indeed the issue this is an easy fix. You simply use sony ps3 hdmi cable which is low end regular old hdmi cable. Or any hdmi non 1.3 cable.

It carries everything need for any content being delivered today thru hdmi and it is not 1.3 spec so it will no comply with 1.3 spec.

There will be no extra lag.
serialmike is offline  
post #12 of 13 Old 07-21-2010, 01:40 PM
AVS Special Member
 
Steve S's Avatar
 
Join Date: Mar 2001
Location: Fresno CA
Posts: 5,356
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 46
Quote:
Originally Posted by davenport47 View Post

Joker says: <<So, I doubt this is the bigger mystery that davenport47 implies it might be, especially on LG TVs. My current thought is that this has to do with the HDMI 1.3 spec's inclusion of functionality for the TV to specify how much audio lag is needed to match the video processing delay which the TV has.>>

Steve S says: <<. . . poor audio synch was very common on HD cable, sat, and OTA signals in the early 2000s, wouldn't surprise me if it's still a problem on some channels or providers.>>

It's becoming clear that lip-sync issues are a complex matter. Joker's problem doesn't apply to my observation about the little Tosh CRT. Yet Steve's does.

Allow me another example: When I had a 47" Samsung (eventually returned for flashlighting), I was watching a standard DVD of an old B&W movie, *Sink the Bismarck*, via a Panasonic Blu-Ray player. The sound was out of sync for about the first 15 minutes of the movie, and then corrected itself! How this can be I have no idea, but I experienced this twice using the Samsung. Other movies have been consistent (i.e., consistently out of sync or consistently in sync).

Anyone have an explanation for how a DVD can start off being slightly out of sync, then get into sync after a few minutes?

Since the "self correcting" sound sync problem with "Sink the Bismark" was repeatable it's almost surely the mastering of the disc. I once had a Sony dvd player (model DVPS-550D, circa 1999) that would occasionally have random audio sync problems which Sony fixed with a firmware update.

Steve S.
Steve S is offline  
post #13 of 13 Old 07-22-2010, 07:32 PM - Thread Starter
Senior Member
 
davenport47's Avatar
 
Join Date: May 2009
Posts: 447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by Steve S View Post

Since the "self correcting" sound sync problem with "Sink the Bismark" was repeatable it's almost surely the mastering of the disc. I once had a Sony dvd player (model DVPS-550D, circa 1999) that would occasionally have random audio sync problems which Sony fixed with a firmware update.

So . . . you've come up with two explanations. :-) I'll have to try that movie again when I buy another TV.

Yet all of this goes to show that owning a Vizio with its lip-sync adjustment makes the most sense (since Vizio's picture quality now equals those of Samsung, Sony, etc. and insofar as I can tell, without flashlighting issues). When are other manufacturers going to offer a lip-sync adjustment? Vizios are excellent, but I still don't like being locked into one brand.
davenport47 is offline  
Reply LCD Flat Panel Displays

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off