Hi @Fredy89 

Welcome to the Sonos Community!

If I understand you correctly, it sounds like your best option would be to only use the TV remote to control the volume. I suspect that if you take the TV off Passthrough mode, you’ll get more control over the volume (passthrough typically means the device will do nothing to the sound feed and simply pass it on). Without Passthrough enabled, the TV will also convert formats that the Arc can’t play to Dolby Digital for it.

With HDMI devices, volume commands are passed along to other HDMI devices, so technically it shouldn’t matter which remote you use. The program remote feature is really for when HDMI isn’t in use (if you use the adaptor for optical output, but you don’t want to do this as it will limit the sound formats you can use).

You mentioned 100% volume - is that what your Arc is at? If so, then you are bound to be deafened at some point. It’s best to keep the Arc volume at a reasonable level and turn other devices up (if they maintain their own volume levels, separate from connected devices).

I recommend you keep eARC mode on.

I hope this helps.

Mmh so you think it might be the passthrough option causing the issue. 

I will turn this off and see what happens to the volume then.

I had it "working" perfectly when I couldn't get the surround sound to trigger. Everything was on stereo pcm. So I kept the Sonos on 100% and just used the small Chromecast remote to change the volume. I never had to use the magic "LG" remote before.

After I found the setting in the Chromecast to use the surround sound...this issue came up. 

I basically would like that the Chromecast device handle's all input. I can then make off setting changes on Sonos app like the speech enhancement and stuff. Even music I will play through my Chromecast rather than Sonos app. Will mess with my current Google home grouping if I add the Sonos speaker separately. The Chromecast is set to be "tv" if I play music and tv is part of group it should just push music through to Sonos bar...still using Chromecast remote for volume.

Will see tonight if the passthrough will this solve it thanks. 

Sorry took so long got logged out of my password manager...took till weekend for me to try and reset my password.

So update... still doesn't work. So to just to reiterate the problem. When sound switch from stereo to high res audio it basically swap from my Chromecast device handeling audio to the Soundbar handling the audio. This means volume is either 100% when swapping and then soft again when swapping back because Sonos bar needs to be on 100% for me to utilize my Chromecast remote fully.

So for another test i actually for completely different reasons was able to swap from my LG 55 nano90 to LG 55 CX OLED. Both are the 2020 model.

Same problem...persist so either 1 it's a built in issue with 2020 motherboards and software (all updated) or it's just a setting I don't know how to change.

I would really prefer to use Chromecast remote but if I can't that will be okay...I don't think it's the remote. When I swap between high res and stereo constant i would like the audio to stay at "50%" and allow me to use same remote to go up and down in volume.

Hi @Fredy89 

It sounds like when PCM is in use, the Chromecast will properly alter the volume, so it is reduced before reaching the Arc which is at 100%. When you switch to Atmos, the Chromecast is deciding to have nothing to do with it and sends the stream straight to the Arc without modification of volume (except when muted, when it just doesn’t send anything).

All I can recommend to avoid getting blasted occasionally is to keep the Chromecast volume up and control volume on the Arc independently. If you wish, you could use a different, old remote just for volume (teach Arc the IR codes) - I appreciate that you want to use the Google remote for everything, but this might be the closest you can get to that. I also recommend you contact Google and report the situation to them too.

Note that with CEC on, your TV remote should be able to do basic functions on your Chromecast as well as adjust the volume on the Arc.

Hi, @Corry P 

Yeah...i figured that my last ditch option would be to just drop the Chromecast remote and use the LG tv remote for everything. I will see if I can set this up this weekend as I'm going to be gone this week.

Its hard to judge the volume of the Sonos. It doesn't have an indication for volume other than on app. So it's easy to go very high with it in stereo mode. Then get blasted when it swapped back to high def.

Also my setting on the hdmi is set on bitrate not PCM? I read online that bitrate setting is best for surround formats.

eARC is on... high def formats are enabled on my Chromecast...will just have to inform google of issue i guess...since this is second tv with same issue this must be a problem allot of people are having? All updated software...2020 LG models?

Thanks eniway will try stuff on weekend and say what I was able to get right.

Hi @Fredy89 

That’s quite unusual - the volume difference between PCM and surround shouldn’t be all that much. In general, however, when amplifying sound you want your source device to output at full volume and your final stage amplifier to control the actual volume. This is the opposite of what you are doing.

I presume you mean “bitstream”? PCM sure isn’t the best for surround - it’s only stereo! You will only ever get stereo if you select PCM as the output format.

To be honest, this exact complaint isn’t one I’ve come across before. 

You’re very welcome, and I hope you get a solution that works.

@Corry P 

I contacted google...after copy and pasting all the stuff above the guy was actually able to help me out.

Google Chromecast with google tv has a ad device section...i have used it before to add a Xbox controller and keyboard...but didn't think it would be needed for a Soundbar...setting it up was quick...and it just worked.

Hi @Fredy89 

Interesting - I would not have guessed that! Thanks for updating us here, and I’m glad you’ve found the answer!

Can you help me understand? Did you add it to connect via Bluetooth? Or do you still have the ability to watch/listen with Dolby Atmos?