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Samsung forum

General discussion

Dolby 5.1 pass through from HDMI input to Optical Output

by dcwinters / February 1, 2009 11:17 PM PST

I have a LN52A630 that I input HDMI directly from a Directv HD DVR. I am experiencing audio sync problems because I have a Home Theater receiver that has no HDMI input and therefore am using Digital Audio Out on the HD DVR to the Home Theater Audio system.

I was thinking that I could cure the sync problem if I sent the audio to the HT receiver from the TV instead of the HD DVR. However, I have heard that some/most/all TVs do not output Dolby 5.1 Digital from an HDMI input. Is this true on the LN52A630?


Discussion is locked
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by Samsung_HD_Tech Samsung staff / February 2, 2009 6:55 AM PST


The only 5.1 output through the optical out on the television would come from the tuner (assuming they are broadcasting a 5.1 audio feed). HDMI surround to the television will only output 2 channel audio via optical.

Your best option is to send the audio from the HD-DVR directly to the receiver, and use the HDMI for the picture.


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by justindthomas / March 28, 2009 3:00 PM PDT
In reply to: 5.1

Is there any hope for change on this item? Perhaps a firmware upgrade or something?

Optical inputs on my sound system (Yamaha YSP800) are limited to two. It would be much more convenient to use the 3 HDMI ports on the 630 for each of my devices and route a single optical connection from the TV. In that scenario, I could actually use all of the capabilities of my media devices.

This seems like an arbitrary limitation - and one that degrades the utility of the TV to the consumer. There's no reason not to use the HDMI digital audio from each device and eliminate the redundant optical connections, other than perhaps licensing costs or something silly like that.

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by Samsung_HD_Tech Samsung staff / March 30, 2009 4:43 PM PDT
In reply to: 5.1


I'm pretty confident in saying that it's not a firmware issue, and it's likely not upgradable since it deals with hardware.

What you're talking about is automatic optical switch capabilities, which is available, but typically an industry add-on to the receiver (versus the television), and not a standard feature on a television. I'm not sure what the details are as to why that decision was made or how it was reached.


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same problem for LN52B750?
by doc3osh / April 25, 2009 10:56 AM PDT
In reply to: 5.1

I assume the LN52B750 also does not pass through 5.1 channel sound via it's digital audio out? That is a real headache... Maybe I am really lucky and this newer model was made the way it SHOULD be??

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5.1 audio
by iheartfirmware / April 25, 2009 1:42 PM PDT

None of the samsung televisions will carry 5.1 audio. You will always be better connecting the audio source directly to the hts. They just don't build the hardware in a way that would pass it through.

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by jerseyboi_27 / October 2, 2010 8:12 PM PDT

yeah this blows.. I had a sony bravia that in fact did have this capability, but it also had an internal surround sound receiver, which is why it would relay (so to speak) 5.1 through optical out.. As far as I know, only hdtvs with surround sound direct hookups are able to do this, as the HDMI handshake between device and tv will only recognize that a standard 2 channel tv only requires 2 channels or stereo sound... it's misleading when a tv advertises Dolby Digital 5.1 but read the fine print.... this t.v. is equipped with an internal tuner (DTV) and D D 5.1.. so if you watch t.v. over the air or direct cable line to t.v. only then will your optical out send the 5.1.... good luck, i've been going crazy

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RE: Dolby 5.1 pass through from HDMI input to Optical Output
by mnyasir / October 17, 2010 3:38 PM PDT

Yes, you can. I know in Samsung TV manual its clearly stated that you can get 5.1 channel sound only from TV Tuner thru ur optical output, but it can output 5.1 channel sound through USB and streaming as well. It only works with media encoded with certain codecs for the USB player to detect and output 5.1 channel sound. Most mkv files with high bitrate can output Dolby Digital sound. All you need to do is during play click the 'Tools' menu button on ur Remote control go to 'Sound Settings' and go to the very bottom of the menu and there you will see 'SPDIF Audio output format' which is by default selected to 'PCM' (2 ch downmix). Click the left or right arrow button on ur remote and you can change it to 'Dolby Digital' (5.1 ch). You can notice the difference once you hear it on ur receiver...

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how about 5.1ch AAC audio from usb
by kannanplus / February 27, 2011 12:45 PM PST

Great! So 5.1ch AC3 works from USB. How about 5.1ch AAC audio? Most MKV files contain AAC 5.1 audio rather than Dolby. Is that sent through optical out or will it be only 2ch output (same sound from all speakers)?

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Yes! Dolby Digital with AVIs and MKVs!
by SillaR / August 24, 2012 8:49 PM PDT

You're right, thanks! On my TV is on a different menu, but it works! Grin

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bravia carries dolby digital but not dts
by hakim0271 / December 1, 2015 3:43 AM PST

I have thé same TV no problem with dolby digital 5.1 6.1 but with dts no signal reaches thé reciver

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This would have been a deal breaker!
by Bhoy0 / December 7, 2010 12:07 PM PST

I have spent a couple of grand on an all singing all dancing Samsung TV with all the inputs you would desire, but no audio pass through! This to me would have been a deal breaker at the store if I'd known this. It just doesn't lend itself to existing setups.

I am pulling my hair out at the fact that such a trivial piece of engineering has not been included! And it is trivial. If the TV is sold as a digital AV hub then it should perform like it. What is the point of even using HDMI if audio signals cannot be manipulated and switched at the users discretion without loss of audio quality within the TV.

Why else would you have 4 and 5 HDMI inputs. HDMI is supposed to minimize and simplify interconnection of modern high bandwidth devices, yet manufacturers (SAMSUNG) suggest the use of additional cables connected to an external receiver for our devices to achieve 5.1 audio. Unbelievable!

I want 1 remote to switch between all the devices connected to my TV with their respective audio directed through 1 output from the TV to HTR equipment. Simple.

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I'd debate that.
by R. Proffitt Forum moderator / December 7, 2010 1:26 PM PST

"HDMI is supposed to minimize and simplify interconnection "

Since it mandates HDCP it is to protect content and in doing so has complicated what does and does not work.

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Xbox360 can do this, so it's not TV's hardware limitation
by tuimonen / December 8, 2010 10:09 PM PST
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Support from Samsung Gives no answer
by Lionel_r / February 1, 2011 11:54 PM PST

Here is a little conversation I had with Samsung's support, regarding my new LN46C750 LCD 3D TV. Please, write directly to Samsung's support (, if we are several to do so, maybe they are going to reconsider making an upgrade:

My frist question:
I can't beleive that you made such a great TV and did not allowed us to choose the Dolby Digital option in SPDIF with an HDMI input!!
Is it the same with the Media player and the USB or WiFi inputs? If yes, this is a real downer and I will not recommand Samsung products.
Will you write a firmware update to correct this bug?

Samsung's answer:
Dear Lionel
Thank you for contacting Samsung Customer Care.

If there is bug, we use firmware to fix it, when that is possible. When it comes to using the firmware to add more option to a 1-year-old model, that is less likely. New features see the light of day integrated in new models.

My reply (a bit more aggressive I must admit):
I was really not satisfied with your answer to my question
So, you're telling me that I have a stunner new model, a 3D model, and that I will have to buy the next new model to may be able to have Dolby Digital out from the optic cable when using an HDMI input?

Are you kidding? Do you think, we, consumers, are this rich? Or stupid?

I'm not talking about a new technology there. HDMI is designed to help us with connectivity by bringing both video and audio and is also designed for High Definition.
Tell me if it is possible that a future firmware upgrade will correct this non sense. Or tell me the reasons why you decided not to give this feature. Don't take me for a wallet and please give me a real technical answer.
I'd like to know why I should keep on recommending your brand to my friends and family.


Samsung's reply :
Dear Lionel Reynaud
Thank you for contacting Samsung Customer Care.

This is the technical support. We can assist when a feature provided with our product does not work. If you want to know why a certain feature was not included in a product, you may need to talk to the marketing department (for this, you can call 905 542 3535 and ask to be directed to marketing) or, maybe, the R&D team in Korea.

I replied to this email, but I think I won't have any new answer.

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Actually it is still the TV hardware
by jc1ward / January 10, 2012 12:06 AM PST

The fix for the Xbox360 does work but only because it stops the Xbox from sending the HDCP handshakes.
You will never get BD player or a Satellite receiver to do that. My understanding on the research I've done is that the HDCP chips are a hard coded devise licensed from Intel.
No Firmware update will fix that.

To C/NET I bought my Samsung TV on recommendation from one of your reviews.
If you had on the review this little quirk I would have never bought the Samsung 46LNA550.
Thank for letting my down.

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the HDCP chips are a hard coded devise licensed from Intel.
by R. Proffitt Forum moderator / January 10, 2012 2:13 AM PST

"the HDCP chips are a hard coded devise licensed from Intel.No Firmware update will fix that."

This is one reason I have never invested much in HDTV gear. The entire industry is bent in odd ways to inhibit things from working that should have worked.

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Sharp vs Samsung vs Sony
by PSM1727 / September 25, 2012 9:34 AM PDT

Sharp also has this problem, neither my sharp 60" or samsung can pass through 5.1 surround sound. My 47" Sony Bravia passes through DD 5.1 and DTS without a problem, I assumed all HDTVs did this. Turns out I was wrong. For those looking for a TV that can do this, save yourself the hassle and buy a Sony.

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Dolby 5.1 pass through from HDMI input to Optical Output by
by DolbyGig / January 21, 2013 8:28 PM PST

Ur damn rite. I would recommend my friend sony product rather than samsung. Just wasting my money and my time. Samsung inventor really an *******.

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Apple TV works
by Ebinpulp / September 22, 2015 11:45 PM PDT

My Apple TV's 5.1 signal passes through my Samsung TV but my Blu-ray, TiVo, and Kodi HTPC will not.

Anyone know why?

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This is buried in a long old post.
by R. Proffitt Forum moderator / September 23, 2015 8:15 AM PDT
In reply to: Apple TV works

There are more than one 5.1 standards. The Apple TV may have used one that worked.

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