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General discussion

LN52650A sound/video sync issue (and google is failing me!)

Mar 15, 2009 7:48AM PDT

Hello -

I'm having sound/video sync issues on the 52A650 I just purchased. I connect my components directly to the TV via HDMI. I use the TV's analog/RCA outputs to connect it (via normal interconnect/patch cables) to my 2-channel audiophile integrated amplifier. The amplifier has no sound delay capabilities and is a straight pass-through (it doesn't even have bass/treble adjustments).

The audio is ahead of the video and I have no delay options downstream. What are my options for fixing this? Can I add delay in the TV itself before it outputs my analog left/right sound? If I can't, I have to return the TV, as I can't justify spending more money on a receiver/delay to fix the issue.

I've been poring over google looking for solutions, to no avail.

Thanks ahead of time!

Discussion is locked

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LN52650A sound/video sync issue (and google is failing me!)
Mar 16, 2009 12:57AM PDT

hausertreyen,

What sources is this happening on? All of them? Or just one of the hooked up peripherals?

Keep me posted.

--HDTech

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LN52650A sound/video sync issue - more info
Mar 16, 2009 1:40AM PDT

Thanks for the response.

I only have two sources for the TV: my Cox Cable DVR and my DVD player. Both are connected via HDMI to the TV, but the issue also exhibited itself using component connections for the cable box (I've yet to test component on the DVD player). I discovered last night that I could connect the DVD player's audio directly to my amp and use the DVD player's audio delay to fix the issue there, but the cable box has no such functionality for me so i'm out of luck on cable.

Now, some stations and programs are worse than others. I don't yet know the correlation between strong, smooth HD signal and lip sync issues vs. weak HD (or good SD) signals...I've simply not had the TV long enough to figure it out, and I'm not sure I have the tools to do so. I'm operating on the theory that the more video work the TV has to do, the longer the delay will be.

I do have an older projection HD display sitting right next to my new LCD that I use for comparison. This has been extremely helpful in figuring out when there are legit sync issues coming from the source (my cable box), but I've only found one such instance of a particular program that had an issue. The rest sync perfectly on my 2nd TV (rear projection) even when going through the amp.

Hopefully this answers your question - thank you!

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LN52650A sound/video sync issue - more info
Mar 21, 2009 11:24AM PDT

hausertreyen,

I've been pondering this one, and wonder if the television itself has the same delay, or if the delay is occuring ONLY out of the analog L/R outputs. I do know that the internal speakers are digital, and to output the audio to the RCA ports in the back requires a digital-to-analog conversion (which is done automatically). This process does have a slight delay, but up to this point, I haven't seen anyone complain about it.

Test your most affected channel with the sync issue by watching it through the receiver for a minute, and then route the sound through the television speakers. Let me know if you can see a difference between those two.

Keep me posted.

--HDTech

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update
Apr 3, 2009 6:26AM PDT

Well, it's still happening. When I route the audio directly from the cable box to my amplifier, the syncing actually gets worse (that is, the audio is even more ahead of the video).

I have a suspicion here, incidentally. My amplifier has an extremely short signal path. There is no DSP - not even any bass or treble controls. I bet that Samsung has purposely put the audio ahead of the video, counting on either a slower signal path through a typical receiver or that the receiver has delay capabilities.

In receivers that slightly delay the audio due to signal path (which you wouldn't think would take long...but even 80ms would be significant), video would precede the audio, and there would be no way to correct for it. (that is, the receiver couldn't delay the video or accelerate the audio) So Samsung takes a conservative approach and makes sure that audio precedes video just a touch, because it's usually not an issue (again, given signal path and delay abilities of today's receivers).

Most of the time, the audio isn't THAT far ahead of the video. I'm no expert and have no way to guess the actual amount of time, but it's enough for me to easily notice it. My wife usually doesn't notice it and only some of my friends do. I think I'm especially sensitive to it because I happen to do live sound engineering.

What's your take?

(as an aside, i bought a Sony V5100 for comparison, and it's audio output is spot on)

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update
Apr 3, 2009 6:20PM PDT

hausertreyen,

I think your suspicion is probably pretty accurate. The "death" of any television line is where the video is delayed beyond the audio. It's much harder to delay the picture.

That said, you might try to go into Just Scan mode or Game Mode, which turns the picture processing off - but then, your picture won't be put through picture quality enhancers.

If you notice it, then I would conclude that this isn't a solution for you. I'm sure there is a way to fine-tune the audio settings somewhere in the service menu, but I can't assist in the how and wheres of that as a policy.

If you've found a unit that "spot on", then go with it. I'd rather you have the experience you're looking for, and consider us the next time around. Happy

--HDtech