LG C9 + Arc + UB820 / Multichannel PCM for DTS Blu-Ray discs

Just installed the update on my LG C1 ( v 03.33.11), and I still have the now famous issue with DTS and Stereo PCM on Panasonic UB820.

Seems that the last update solved the problem on LG C9 and CXseries but not on C1 and C2 :-( 

The good news is that this update show that the issue is on LG side and/or can be fixed by LG… on products that still receive updates 🙂 (considering the fact that a new firmware update for the UB820 will probably never happen, it’s a good news).

Just hope that a future new firmware update will solve the issue on LG C1 and C2 series.

For the price of an ARC and an a Arcana your are not far off a Sony HT-A7000 and no issues at all. Hard choice to make..

There’s a comparison of those two soundbars here from rtings.com…

https://www.rtings.com/soundbar/tools/compare/sonos-arc-vs-sony-ht-a7000/13760/27046?usage=8767&threshold=0.10

It’s not really the point here, considering the fact that the issue we’re talking about is due to the Panasonic UB820 coupled with a LG C9 / CX / C1 / C2.

There’s no debate here about the choice between an Arc or another product ;-) 

I’ve just checked my C9 and UB820 and still receive PCM Stereo rather than PCM Multi channel (I get LPCM multi channel for my PC and PS5). Is anyone now receiving PCM Multi channel rather than stereo when playing DTS HD MA blu rays/4ks through their player?

Mixed feeling about it. It seems that the last LG update has solved the issue in some cases, as for @movie_monster for ex, but the issue is still here for others, like me.

It’s clearly a problem between LG Oled TVs and Panasonic UB820 player; has changing the player (for a Sony X800-M2 or an LG UBK90 for ex) will immediatly solve the problem, as changing the tv (tested on a Sony 55A90J on my side).

So a specific handshake issue between UB820 and LG Oled TVs seems to be the explanation; meaning that we need Panasonic and/or LG to update their firmware to definitly resolve this problem.

For information, I had an open ticket with Panasonic support since couple of weeks, with lot of Q&A by email with their support agents, who where in contact with internal software engineers (at some point I have gave them the link and it seems that they have read this topic).

Here is their final conclusion :

« The factory has been notified. Their point of view is that the problem is with the TV, not with UB820: The recorders do not have EDID. The TVs have EDID and update the audio part with the EDID of the Sonos sound bars. If the problem disappeared by converting the EDID of the TV with a special device, the EDID is "corrected" to conform to the HDMI standard. »

So, for Panasonic, the issue is on LG side.

By the way, this point from Panasonic support team may interest @GuitarSuperstar , who was deeply involved in this topic at some point 😀

I’m confused : I bought an LG UBK90 to replace my Panasonic UB820 in order to be able to play my DTS BluRay disc in 5.1 PCM through my LG C1 and my Sonos Arc…

… and my DVD and BluRay DTS tracks are still playing in 2.0 PCM.

My UBK90 is set in Multi-Channel PCM, then I try to set the tv in bitstream and PCM but I still obtain Stereo PCM as a result.

Did I miss something ??

Be sure the TV settings are set to this:

HDMI Input Audio Format - Bitstream

Digital Sound Output - Passthrough

eARC Support - On