LG CX + Bose Soundbar 700 + Apple TV 4K = sound dropouts


Novice Member

recently, I bought myself a Bose Soundbar 700, as new sound source for my LG OLED 55CX 2020 model. I have connected the Bose Soundbar 700 via (e)ARC to my TV's HDMI 2.1 port 2 (which also supports eARC).

I am watching all my streaming services (e.g. Netflix, Amazon Prime) with my Apple TV 4K, which is connected to HDMI Port 1. On HDMI port 3 I have connected my Playstation 4 gaming console.

The Problem:

When I am getting ready for a movie and display my Apple TV's content on HDMI 1 port, I get sound dropouts in the first 1 to 2 seconds from all present sounds in the main menu. Means, from the key icon sounds when browsing through with the remote control. Also when browsing through the Netflix applications main menu. However,- if I, for example, keep scrolling through the Apple TV's home screen or Netflix main menue for longer than a second without interruption, the sound comes correctly as expected and stops dropping. But if I stop and wait for a second or two again, the sound drop begins again for the first seconds. It feels like as soon as I wait, the first sound gets somehow swallowed. It seems to be related to the PCM settings.

This problem occures only on my Apple TV 4K. However, if I change the sound settings on my Playstation 4 to "PCM Linear", the same issue occurs on the gaming console.

What I have checked so far:

- Software versions (all up to date)
- HDMI cable (all cables are "Ultra High Definition HDMI" cable's with 48gbp/s)
- Replaced the Soundbar with my Bose Lifestyle 650 systems (same sound dropouts)
- Changed and tried all display settings from Dolby Vision to lower resolutions (e.g. HDR, SDR)
- Changed and tried different audio settings from LG TV and Apple TV (e.g. to Stereo)


Have you any hint how to solve this?

Did you read or faced the same issue with Bose, LG and Apple TV 4K?

Is this related to some HDCP handshake issue?


Distinguished Member
The Bose soundbar 700 only supports eARC on paper.

It's audio formats are all limited to the same audio formats of ARC so its not a good idea to use the eARC mode as this enables sending audio formats the bose 700 cannot handle.

eARC on the LG supports PCM 7.1 audio, the ATV4K and PS4 detect this and try to send PCM to the Bose 700.

Disable eARC on the TV stick to plain ARC output, on your devices set them to pass Dolby 5.1

Though if you experience audio lag set the PS4 back to PCM 2.0 (stereo) which is supported in ARC.


Novice Member
Hello @next010,

even if your answer sounded very professional, it did not worked out. I have disabled the „eARC“ Button on the CX and set the Audio Format in my ATV4K to DD5.1.Even after restarting all 3 devices, the error occurred still.


Distinguished Member
Did you also change the LG sound setting from pass-through to auto, I believe that is also required for correct HDMI-ARC configuration.

If the problem persists change the ATV4K back to auto in its sound settings and see what happens.


Novice Member
Hello @next010,

I have followed your instructions. The error unfortunately is still present. Do you think it might be related to my HDMI cables? I have 48gbps HDMI cable with 3m length in place. The brand is "CableDirect" / "KabelDirekt".


Distinguished Member
It's possible, there's no harm in trying some other cable.

Try using a certified premium high speed HDMI cable, there are no certified 48gbps cables.


Novice Member
Hello all,
Just bought also the 48CX perfect screen but... want the audio over the Marantz SR 7007 (in the future want to purchase the Bose 700) in the dashboard the shows the 7007 also the marantz menu is there but no audio what so ever tried all the settings for the last days, now there is the toslink that works , use the high speed with network HDMI cable , marantz has 2 arc inputs. anybody any idea?

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