They are all set from the factory to PCM only. However. All these sets can pass Dolby Digital as well. It just needs to be enabled in the service menu. PCM to AC3. Then another change has to be made in the service menu. The new AC3 setting. It has to be written to all 4 HDMI ports. I know many many owners have complained about these tv's only passing PCM. And I know other brands. While very few. Can pass it as well when its factory enabled. Some what of a holy grail when you get a tv that can actually do it. These are my notes from a previous post. But, I wanted to make an official thread to get this word out for LG owners out there with 4k sets.

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Just an update. I followed through with LG allowing the tv to pass Dolby Digital. Not just PCM. It can be done on all 4k LG tv's. It is simply disabled from the factory in the service menu for LG does not have to pay Dolby Digital licensing fees. That is my guess. Or people simply do not care enough and LG leaves it disabled because of that. I am using HDMI ARC with my LG soundbar as well. Picture attached for proof. My soundbar also confirms Dolby Digital is being used. So, everyone saying these tv's are just limited to PCM and will only pass that. Using HDMI or Optical. It is completely false and needs to be addressed in the service menu. LG will do this for you for free as long as the tv is under warranty. The tech just left the house a few minutes ago.

I also wanted to add. Since the tech. here had direct access to LG techs. These guys even have access to the actual television models while working on the phone with them as they go. I asked if a firmware update would revert the previous settings back. He said absolutely not and they stick when making changes like that in the service menu. I would also suggest not doing something like this yourself. One false move in the service menu and you will have a big expensive brick. Call LG instead and they will be happy to get this set up for you and have someone come out. I have the LG 65UB9300 4k tv.

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I have the 55ub9500 and the sound setting is set to auto in the sound setting. I get Dolby digital from the roku and all of the TV apps just fine. I can't get Dolby digital from the htpc though.

My response here for others. https://www.avsforum.com/forum/166-lc...l#post33694681

Ok this works for external devices. Even my Samsung can't do this.

My Samsung will ONLY deliver DD 5.1 through the optical port IF the source is coming from the coaxial RF.

An exception to this is if you have a Samsung smart TV, then they say it can deliver 5.1 through the optical digital port.

I tested the cable box and the roku attached directly to the tv by way of HDMI and the Samusng would not pass 5.1 to the amp by way of the digital optical cable.

WHY would I want to connect the cable box to the TV instead of the amp? To make it easier for a family member to watch cable tv, *without* using the amp... So, I get the cable box 5.1 through the amp by way of the optical cable from the cable box. I just won't be able to get 5.1 from any OTA transmissions, since the amp's two optical ports are now taken...

Here's how Samsung describes the TV's limitation:

http://support-us.samsung.com/cyber/...UN46EH5000FXZA

Thanks i got it working perfectly and it wasn't to hard, but like you said if some aren't tech savvy just let lg handle it. there is a lot that can get screwed up.

I am definitely able to get Dolby Digital back in ARC from The 2015 Vizio M-series TV. Not sure how to get it back from an external device though. Or even why I would want that? Is it necessary in cases where your receiver doesn't support the video from your external device but it does support the audio?

I guess I could use the 2nd output of my Blu-ray player to go through the TV and bring the Audio back to the receiver with ARC. However, I could just send the video out one output and the audio out the other which is a whole lot simpler.

Is this truly passing through Dolby Digital or is it converting DD to PCM and back to DD? Hence the parameter name PCM to AC3? Wouldn't you rather have PCM than DD? DD is lossy and PCM is lossless?

ARC can easily handle DD (5.1), just like an optical connection can, but that's it. Neither connection can transmit HD audio. Most tv's nowadays can do that when using the internal ATSC tuner for either OTA television or cable tv (both via coax). There are only a few tv's that can take an external source connected to the tv and pass DD 5.1 to a receiver.

I need to switch settings over from pcm to ac3 to overcome audio lip sync issue with roku 4 media streamer. Can anyone tell me how to access the service menu please?
I have a 65ub9200.
Thanks

But are there broadcast in 4K??

yep:
http://www.techradar.com/news/televi...proved-1256181

Hi, is there a tutorial for this? I am very comfortable playing around in the service menu, I calibrated tv's for awhile, if not can someone supply me with the service menu access codes

thanks

I have optical only input on my new soundbar and really need to switch the TV over to AC3 5.1 passthrough for HDMI from pcm.. escpecially since now that I've had the HDMI 2.0 upgrade done I lost the ability to use ARC. Anyone in NY had this done yet by a tech in the service menu or know how to do it? I am very comfortable doing it myself if I can get into the menus - Calling LG Customer Service today to ask as well since my set is covered under the VIP care -

thanks in advance guys!

Hey guys, so I was overanxious and couldn't wait for the LG service remote so I bit the bullet and called LG customer service to switch over the TV output from PCM to AC3 which after writing all changes to the HDMI ports has allowed Dolby Digital output over the optical connection of my 65LA9650 4K TV. Only need one cable from TV to new Yamaha ysp-2500 and can I tell you how amazing it is to hear true 5.1 from my cable box/netflix/hulu/ps4 and all connected external sources. The soundbar is truly amazing because i have an unorthodox shaped room where you wouldn't think the digital sound projection would work but let me tell you it works very well! thanks for all the info on switching over the PCM output... the LG tech wasn't aware that this change made the difference because he said the TV should figure it out if set to auto.. since I paid the 180.00 for the service call he had to indulge me and try it with the change and to his shock it worked! wish i didn't have to pay for the call but its a 2013 model so basic warranty is over.. so happy its all working now i could care less about the money!

thanks all!!!

What two settings were changed. I found one. Whats the other?

I was able to get into the service menu and change the setting from PCM to AC3, but could not find the area where you apply this setting to the HDMI ports. Does anyone know where this is?

Did you ever figure out the other one?

I got in with the Harmony hack and changed the setting to AC3 on my LG 50LN5600. I didn't have to apply the setting, it just worked. I changed it, hit exit, and turned the TV off and then back on.

Not only does it work like a champ, my cable box was apparently putting out 5.1 but the TV was piping 2 channel right back to the sound system. It sounds awesome now. I mean, it's a hugely noticeable difference.

Hmm. I have a 70UF7700. I changed the setting to AC3 and have power cycled the TV multiple times, but passthrough still comes out as 2 channel instead of 5.1. Some other guides mentioned EDID D/L, but I definitely don't have that option (I've dug around in the EZ_Adjust and INSTART menus for hours looking for anything similar).

I'm stuck and it's creating a situation where when I use the Netflix app, my sound system changes to the TV out signal (which comes out as 5.1), but when I exit the app, it doesn't change the sound system back, so I have picture and no audio until I manually change the input on my receiver. I'd like to utilize passthrough like I did with my old TV but I'm not going to sacrifice 5.1 to do so.

Oddly enough, it just started working today. I still can't get my PS3 to do anything but stereo, but HDMI port 1 which is my set top box is doing Dolby now.

I'm planning on trying this tonight on my 60UF7300 via the Logitech Harmony method - I'm confident that I'll be able to figure out how to switch the PCM setting to AC3 easily enough, but can anyone provide any further clarification as to what needs to be done for the second step, where AC3 is applied across all HDMI ports?

It will be an option in the EZ_ADJUST menu. If yours is like mine, and it isn't there, you probably don't have to do anything other than reboot the TV.

Well I accessed the service menu and changed the option under tool option 7 from PCM to AC3 easily. I couldn't find any other option in any other menus related to applying it across all the HDMI ports. I have 3 components connected to my TV via HDMI and an optical out going to my AVR.

I rebooted my TV, and when my TV and Tivo box came back on my TV indicated in the top left corner that it was receiving DD from the Tivo box (rather than PCM as it used to), and "Dolby Digital 5.1" also scrolled across my AVR's screen with the DD logo illuminated, but the thing is despite all of this I'm only get stereo audio through my from L and R channels. I'm a bit stumped here only getting audio through 2 channels, even though all signs point to DD 5.1 being passed properly through the TV, and out via optical to the receiver's optical in (with the service menu option set to AC3). Any suggestions much appreciated!

Strangely, over the course of the past couple days all cable TV channels have now started playing Dolby Digital correctly. My Xbox One and Apple TV are also properly passing DD, so all inputs are working. No idea why it was only outputting stereo at first, since I haven't changed any connections, but glad it's working now and very happy with the new functionality.

This is exactly what happened with me. I was getting frustrated trying to get it to work, then one day it just started behaving properly even though I didn't change anything.

Well, or so I thought it was working properly. It did for around 5 days - I could watch TV for hours on end and every channel would have a clear DD 5.1 signal the entire time.

But now, whenever I turn my system on to watch cable TV, everything does work as it should for the first 3-4 minutes, DD 5.1 is passed and I can change channels at will, etc. But then, suddenly out of no where (the channel I'm watching has no bearing) the sound will drop out for 1-2 seconds, the receiver will pick the signal back up, but now only on PCM Pro Logic II. From there, no matter what channel I change it to or how long I sit and wait, it refuses to pick the DD 5.1 signal back up and will only pass the lower quality PLII. The only way for me to get a proper DD signal again is to completely shut down my system, then boot it back up. But even then, DD only works for the first few minutes, then cuts out for a second and switches to PLII.

My AVR is a Sony STRDH520 which I know is pretty low end (saving for a better one), but I don't see why it would have a problem with a DD 5.1 signal from a standard Tivo cable box. My TV is an LG 60UF7300 and I enabled AC3 passthrough via the service menu. I have my cable box hooked into HDMI port 2, and I have an optical cable carrying all sound from my TV down to my AVR.

Thanks for any suggestions! And happy weekend to all.

I ran into a similar behavior when I did not change inputs (see below)...

I'm using a HTPC with my 55EF9500 via HTPC -> HDMI -> EF9500 -> HDMI(ARC) -> Yamaha RX-V371... I have changed the service menu setting to pass-through AC3 and I can confirm that on my 55EF9500 the single service menu setting works after a TV reboot. However, I have the following problem.

I use my HTPC as my primary video source so normally I turn my on the TV & HTPC together and all was happy. The audio content from the HTPC made it to my AVR as 5.1 DD with no issues. However, after I played Netflix via the LG, I turned the input back to the HTPC so as to be ready for the morning, confirmed working HTPC 5.1 DD, and powered down. Upon power-up, DD AC3 audio content from the HTPC is silent and the AVR continues to display PCM (PCM is working however). I can easily restore the DD pass-through by changing the source on the LG to TV or the Blu-ray player and then back to the HTPC. This is a minor annoyance for me, but not very acceptable for my technically challenged wife.

This has now happened twice after using Netfix and proper behavior was restored after a "factory reset" (END-IN service menu) until I watched Netflix again.The issue seems to be with the TV and not the HTPC.I have tried to use Eventghost and my HDMI-CEC adapter to automatically switch the inputs on the TV but it seems the commands cannot be push-up to the TV and are ignored...

I have contacted the LG Tech to come over to the house to make the change to AC3. Does this mean then that I will get 5.1 directly from the TV if it is broadcasting in that format

Hi, I have the 60UF8500 4k and can't find how to enter service menu. I saw many people saying they have access to service menu but don't have idea how to do it. The old tutorials says to keep ok pressed on TV and remote control at same time, but the new models will turn off the TV if we try to do that.
Please, cans someone explain how to do it? A nice tutorial with steps would be very appreciated. Thanks in advance!