LG CX 'Optical + Internal TV Speaker' setting isn't Dolby Digital?


Well-known Member
I'm just connecting up an LG 55CX. For general viewing I just use the internal TV speakers and think they're fine - and 'wife friendly'.
I also have a 'simple' AV setup (an old Acoustic Energy Aego P5) that gets its input from Optical - no HDMI ports at all. Again, it does me.
Previously I had a Samsung and it output sound via TV speakers and also via optical simultaneously. I would only use the external speakers when watching from external sources - a Firestick or a PC - both connected via HDMI. I just turned the TV speakers down and got full 5.1 Dolby Digital or DTS through the AV Speakers.
So, I'm now setting up the LG and noticed a separate Sound option for 'Optical + Internal TV Speaker'. Sure enough, the sound is output to both sets of speakers.
However, I can't seem to get surround sound with this setup? Am I doing something wrong? My amp just displays PCM. The HDMI Input Audio Format is set to Bitstream.
If I switch the Sound output just to Optical, the amp displays Dolby Digital and I get proper 5.1 DD. Is there anything I'm missing here - or do I need to keep switching between internal speakers and optical? I do have a Harmony Elite - I assume there are no direct commands available either.


Standard Member
Hi i set optical out in advanced options to mpeg and all sorted now every input works with Dolby digital from sky xbox and amazon prime Netflix etc


Well-known Member
Hi, not sure where you mean for 'Optical out'.
I needed up creating Sequence on the Elite that navigates to select either Internal TV Speaker or Optical. Digital Sound Out is set to Auto.
The only mpeg setting I see relates to DTV Audio.


Novice Member
Hi sjw, I have the same problem, did you find a solution for having a ( wife friendly ) permanent internal speaker on LG65 and at the same time having dolby optical output available for the main amp. if required , without having to change settings ?
I have tried using the 'internal speaker +optical ' setting but cannot get dolby from the optical...it is stuck on 'dual channel', optical on its own works fine, surely there must be a way ?


Well-known Member
Hi, no, unfortunately I never got a good solution. There doesn't seem to be a discrete code to enable the speaker option you want (like you can do for HDMI source). I still find it strange that with both speaker options selected that the external output isn't DD - unlike the 5+ year old tv it replaced.
What I did is I created a macro on my Harmony remote that basically recreates the manual button presses to go into Settings, Down, Right, down etc... It usually works but occasionally, if the TV is a bit slow responding the programmed options end up switching the picture to Energy Saving mode or something! :facepalm:
The other thing that winds me up is the button to switch to TV Source isn't really that at all - if you are already on TV it switches to Radio mode and I can't see any way of disabling the Radio that I have no interest in. This means, on the Harmony, when it switches the TV on and it's told to be on the Live TV option it switches to Radio :( Again, a workaround is to make it go to a specific TV Channel (eg 101) but it's not really ideal.

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