Video/Audio Lag through HDMI

This past weekend I bought an LG 42LH40. I also got Dish Network upgraded to HD and got a new receiver (622 DVR duo). I have an HDMI running out of the receiver straight to the TV. I've noticed quite a bit of lag between the audio and video on most HD channels no matter if it has been DVR'd or is live TV. The SD channels seem to be ok. The sound is definitely behind the picture.

I then ran standard red/white RCA cables from the dish receiver out to my Onkyo audio receiver in and the sound from my audio receiver matches the picture and the TV audio echos the audio receiver audio. Probably a good 1/2 second to a whole second delay.

So I'm wondering if this delay is originating from my Dish receiver or is happening in the TV? I would think by now there would be an update from one or the other considering I saw similar problems being discussed in '06. Also, does anyone know if it is possible on an LG TV to tell the TV to use HDMI video and RCA audio? I don't have a fiber audio cable but I wonder if I connect my dish receiver to my Onkyo audio receiver if there will be the same delay. I appreciate any pointers or suggestions. Thanks!

check your 'audio sync' in the dish menu...it should be set to hd...

i still have this problem occasionally. a guy in-the-know said that it was a signal strength issue....the actual dish positioning was not maximized for optimal signal strength (a common problem)....

Thanks for the advice! I tried that sync setting last night and toggled it back and forth from HD to SD and the TV audio is still behind the video and what I get out of the RCA cables. It actually seemed like setting it to SD sync was less of a problem, but there is still a noticable difference when watching someone speak. They put a new HD dish on my house on Sunday and said I had pretty strong signal strength, but maybe there is an issue there. I would think if the signal was weak though I wouldn't be able to get the correct audio through the RCA out as I am? Strange.

Thanks for the advice! I tried that sync setting last night and toggled it back and forth from HD to SD and the TV audio is still behind the video and what I get out of the RCA cables. It actually seemed like setting it to SD sync was less of a problem, but there is still a noticable difference when watching someone speak. They put a new HD dish on my house on Sunday and said I had pretty strong signal strength, but maybe there is an issue there. I would think if the signal was weak though I wouldn't be able to get the correct audio through the RCA out as I am? Strange.

the guy stated (& he had an extensive website discussing the info.) that what dish claims is acceptable, or "strong" signal strength, is often not. it was his opinion that oftentimes, the signal could be increased with a little extra work...work that is rarely performed during installation. i haven't verified this yet, since it's not a huge problem for me (although an annoying one, when it happens)....

i'll have to look up the thread that this info. was on, later....

Use an optical connection from receiver to your surround sound, RCA is a waste of audio, all you get is stereo, with optical you get DD 5.1.

Also, just from my experience, I bought an LG LH90 and there is a known issue with them having audio/video lag. It was so horrible I had to take it back and I got a Panny V10 instead.

Also, just from my experience, I bought an LG LH90 and there is a known issue with them having audio/video lag. It was so horrible I had to take it back and I got a Panny V10 instead.

Good decision!!! :yippee:

the guy stated (& he had an extensive website discussing the info.) that what dish claims is acceptable, or "strong" signal strength, is often not. it was his opinion that oftentimes, the signal could be increased with a little extra work...work that is rarely performed during installation. i haven't verified this yet, since it's not a huge problem for me (although an annoying one, when it happens)....

i'll have to look up the thread that this info. was on, later....


deepBLUE - the guy in question wouldn't have a name that sounds like 'Hai Deph Geoff' by any chance would he? If so, he blames EVERYTHING on low signal level - even your beer not being cold enough…

I have a tiny bit more time for his theories than many people do, like for example I could believe that picture quality could be degraded if the signal is right on the very threshold of acceptable, because the error-correction mechanisms will be having to work harder and some resulting binary word values may be interpolated rather than actual (?)

But if your video is free from pixellation, glitches, dropouts and macroblocking, even I can't believe that received signal strength or quality could be responsible for making the audio lag behind the video by a second!
Particularly if you can find an SD channel that is fine and which happens to be coming from the same transponder on the same satellite.

Looks like this is an LG HDMI problem. Found this recent post on a best buy forum (I guess I can't post links until five posts). Bunch of people having the same problem all with LG TVs. I called LG and they should be sending out a tech to upgrade my software. People mentioned on this other post that LG originally was sending out flash drives with updates, but now have technicians come out and do the fix. I guess in the meantime I'll buy some component cables which apparently don't have the problem or simply run through my audio receiver using the RCA's until I get a fiber optical cable. Thanks for the suggestions.

Post Number 4

Post #5 - sorry, posting the link next

Here is the link incase anybody else wants to read it: http://forums.bestbuy.com/t5/TV-Home-Theater/Lip-Sync-problem-with-LG-55LH90-using-HDMI/td-p/44561/page/20. Also there is a setting on the LG's that lets you adjust the Lip Sync amount which is sometimes set at 20. One person set it to zero and solved his problem, but then some others figured out with newer firmware, you can't get to that setting without a special LG Tech remote control.

deepBLUE - the guy in question wouldn't have a name that sounds like 'Hai Deph Geoff' by any chance would he? If so, he blames EVERYTHING on low signal level - even your beer not being cold enough…

I have a tiny bit more time for his theories than many people do, like for example I could believe that picture quality could be degraded if the signal is right on the very threshold of acceptable, because the error-correction mechanisms will be having to work harder and some resulting binary word values may be interpolated rather than actual (?)

But if your video is free from pixellation, glitches, dropouts and macroblocking, even I can't believe that received signal strength or quality could be responsible for making the audio lag behind the video by a second!
Particularly if you can find an SD channel that is fine and which happens to be coming from the same transponder on the same satellite.

that sounds familiar...

i just don't really know...my point-dish signal strength is decent (although not what i would expect); but i've never tried adjusting it.

i have a polaroid 46", & a 622 dvr....and when i got everything installed, i was shocked at the audio lag. i was also plenty hissed off, and spent a lot of time trying to fix the problem. the problem existed on component & hdmi cables.

the problem seemed to decrease over time (plus, i got sick of checking if lips matched words); it still happens...but more rarely.

sometimes pausing the dvr for 10 seconds or so seems to help. i used to take for granted that audio would match video.

Unlike analog TV where the screen and loudspeaker was outputting 'live' the signal as it was being broadcast, lip sync is a particular problem for digital TV, where the audio and video signals are packetized separately, sent serially in time, and then must be reconstituted to be presented to the viewer at the same moment. There is more opportunity for the two signals to end up being presented to the viewer at NOT quite the same moment.

The following are snippets from what you'll find if you search for "presentation time stamp" in Wikipedia:

An example of transmission (broadcasting), reception and playback that can get the AV-sync incorrectly synchronized:
There is extensive use of audio and video signal processing circuitry with significant delays in television systems. Particular video signal processing circuitries which are widely used and contribute significant video delay include frame synchronizers, digital video effects processors, video noise reduction, format converters and MPEG pre-preprocessing.

MPEG-2: Presentation Time Stamp (PTS), Decode Time Stamp (DTS)
Presentation Time Stamps (PTS) can be embedded in MPEG-2 (don't know if they are in MPEG4?) to avoid AV-sync drift.
Unfortunately these time stamps are often added after the video undergoes frame synchronization, format conversion and pre-processing; thus those delays remain uncompensated.


Audio video sync error can be annoying to the viewer and can even lead to programs not being effective and to the subject being perceived negatively. The lack of effectiveness problems are of particular concern when product commercials and political candidates are viewed. Television industry standards organizations, such as the Advanced Television Systems Committee, have become involved in setting standards for audio video sync errors.

Because of these annoyances, AV-sync error is of concern to the television programming industry, including television stations, networks, advertisers and program production companies. Unfortunately the advent of high definition flat panel display technologies (LCD, DLP and plasma), which can delay video more than audio, have moved the problem into the viewer's home and beyond control of the television programming industry alone. Consumer products companies now offer audio delay adjustments to compensate for video delay changes in TVs and a/v receivers, and several companies manufacture dedicated digital audio delays made exclusively for lip-sync error correction.

A/V sync errors are becoming a significant problem in the digital television industry because of the use of large amounts of video signal processing in television production, television broadcasting and pixelated television displays such as LCD, DLP and plasma displays.

A source of significant video delay is found in pixelated television displays (LCD, Plasma display, DLP) which utilize complex video signal processing to convert the resolution of the incoming video signal to the native resolution of the pixelated display, for example converting standard definition video to be displayed on a high definition display. "Lip-flap" may exceed 200 ms at times.

if that's the case, it's unfortunate that some of these issues were not anticipated....

i've learned to live with the problem; but that's only because it is occasional...

You're doing it wrong. Do it like this and this made no lag for me.

Plus the hdmi into your tv and run the audio OUT of your tv. Most hdtv's have an HDMI audio out. Run it from that to your surround sound system. Don't run it from the receiver. I get no lag.

In my case I run rca cables because I prefer it over the digital out. Digital isn't as loud and I just don't like it as much. It doesn't push my sub woofer as much. Of course I don't get true surround but I like all my speakers up front anyway. I got hdmi out on both my hdtv's with rca.

with directv I had lag all the time. I'm getting 0 with dish network.

You're doing it wrong. Do it like this and this made no lag for me.

Plus the hdmi into your tv and run the audio OUT of your tv. Most hdtv's have an HDMI audio out. Run it from that to your surround sound system. Don't run it from the receiver. I get no lag.

In my case I run rca cables because I prefer it over the digital out. Digital isn't as loud and I just don't like it as much. It doesn't push my sub woofer as much. Of course I don't get true surround but I like all my speakers up front anyway. I got hdmi out on both my hdtv's with rca.

with directv I had lag all the time. I'm getting 0 with dish network.

Sorry, most TV's do not have an HDMI audio out...

Sorry, most TV's do not have an HDMI audio out...

They don't? Every tv i've messed with has. My dads, my moms, my friends, my two tv's. All different brands.

So, I took it that most tv's had an audio out. Which will output hdmi or any other input on the tv. Mine has a specific HDMI audio-out. The ones I've seen that didn't had just an audio out that outputs everything.

They don't? Every tv i've messed with has. My dads, my moms, my friends, my two tv's. All different brands.


That is an incorrect statement as very few if any TV's have HDMI outputs.

That is an incorrect statement as very few if any TV's have HDMI outputs.

I think you're confused here man. It is the HDMI audio output. It outputs the audio from what's being put into the tv with an HDMI cable. It's not an HDMI output.

It is rca outputs that output the audio that's being put into the tv with hdmi. It's labeled on the tv "HDMI audio out" I will take a picture if you really want to nit pick.

WOW you finally got it. It is not a HDMI output but an analog or digital audio output.