Using LG OLED65C7P with SONOS Beam via HDMI-ARC and Bose QC Bluetooth Headphones.
I paired the headphones to TV, but when I switch the audio output on the TV to "LG Soundsync / Bluetooth", the Bluetooth Headphones work momentarily (3 seconds), then automatically switches back to the Beam on HDMI-ARC. The Bose Headphones still show connected but Beam steals the audio back.
There is a workaround, by going to Settings, Sound, Sound Out, and turning off "Simplink (HDMI-CEC), but this is a pain to do every time I want to use the headphones. You have to re-enable this setting to use Beam again.