Apple TV Volume control not working properly VIA eARC.

@Anthony wrote:

That unfortunately, did not work. Also the function is also available in the iOS Apple TV remote via the control center but even through the control center the function for volume down does not work only volume up. I also attempted to update the firmware of the remote with no luck - connected to power over night and firmware stayed the same not sure if it is on the latest firmware or if the update is not pushing through.

Well that’s too bad… Since the volume control issue is consistent using both the Siri Remote and the iOS remote, this points back to soundbar or TV settings.

All I can suggest is that you take a closer look at, and verify, all of the sometimes-elusive HDMI CEC-related settings on both the TV (LG calls it SimpLink) and the soundbar (Samsung calls it Anynet+ :-). I’ve seen some devices break CEC into several options... On the ATV4K it’s just Settings > Remotes and Devices > HOME THEATER CONTROL: Control TVs and Receivers = On (I’m pretty sure you’ve got this already:-).

Also, have you tried connecting the ATV4K to an HDMI input on the Q950a rather than the TV? I gather it passes HDR and Dolby Vision correctly (even though Samsung doesn’t really do Dolby Vision?).

All else fails, give Apple Support a call… and here’s their recommended reading: If you can't control your TV or receiver with your Apple TV Remote - Apple Support.