Soundbar 700 eARC Issues with LG C9 OLED

[prasadduvvi]

I'm facing an issue with my Bose SoundBar 700 and LG OLED C9 TV. This issue has started in June 2020. There will be "No Audio" from Netflix, Prime Video etc applications. 

My LG TV's sound setting has below two under HDMI ARC and it is causing "No Audio" from Netflix, Prime Video etc applications. 

Digital Sound Out set to "Auto"

eARC set to "ON" 

I've turned OFF the eARC and everything is working fine (It's been close to 8 days and everything is fine so far). I've tried so many different troubleshooting steps, working with multiple technical members from Bose but it didn't work. Finally, ended up with this solution of turning off the eARC in the TV's sound settings. 

I believe Soundbar 700 does support eARC so, I'm suspecting that the HDMI cable that I received with the Bose product in Nov, 2019 doesn't support eARC ?? Do you agree with this? If yes, I need to look for a new HDMI which supports eARC and try. Please advice!

Thank you in Advance!

Product: Bose Soundbar 700 & Bose Bass Module 700

Location: USA

Firmware Version: 10.0.10-8565+88f8514

[Keith_L]

Hi prasadduvvi,

Welcome to the Community, thanks for posting!

You are correct that the Soundbar 700 supports an HDMI eARC connection, however, there are a couple of things that could be stopping you from using the eARC setting on your TV with the soundbar.

The first thing I would recommend looking at when you have the eARC setting enabled is what audio format is the TV using. The soundbar is capable of supporting Dolby Digita, and DTS, PCM 2.0 to PCM 5.1 (multichannel PCM support requires an eARC HDMI connection). If your TV is using a format other than one of these when you enable eARC, then you won't get sound from the soundbar. Your TV's audio/sound settings should have an option to choose the format being used, so you will want to check there to find out the format being used by the TV. 

It is also possible that the TV is enabling a form of High-bandwidth Digital Content Protection (HDCP) when you enable eARC, this can stop audio from the apps like Netflix being able to be sent to a soundbar or other 3rd part audio device as the HDCP is trying to stop you from copying the content. To find out if your TV does have HDCP when eARC is enabled, you would need to reach out to LG, as they will be able to let you know, and let you know if there is any way to disable the HDCP.

I hope this helps, let me know!

[prasadduvvi]

Hi Keith,

Thank you for your response. My TV has two options under the HDMI ARC - Digital Sound Out, Auto and PCM and they support below audio formats.  HDMI supports audio configuration great than 5.1 channels

here is the reference link, https://www.lg.com/ca_en/support/product-help/CT20098005-1437136302910 

[V]

Hi,

it is most likely due to the fact that within Auto mode the TV is sending a Dolby Digital Plus signal from the apps to the soundbar. As the soundbar does not support this format, then no audio will be heard. 

You can try and test this theory by setting the TV to PCM where it will decode the audio before sending to the soundbar. 

The question is whether the tv will decode PCM as 2.0 or 5.1. 

[prasadduvvi]

Hi,

Thank you for your response. I will try that now and let you know.