LG WebOS select_sound_output breaks sound

Configuration
1

The following script

service: webostv.select_sound_output
data:
  sound_output: lineout
  entity_id: media_player.lg_tv

Switches sound output according to menu - it is visible that setting was changed actually, but the moment it switch grey “stop” sign displayed on righthand side of the screen and sound appears no longer available.

I can switch it to, for example, to external_arc with similar script, but there won’t be any sound until I switch TV off with the remote and turn it on again.

Another observation that neither volume, nor mute buttonswork any longer, switching output manually with remote is working, but actual sound remains non-operational. Till TV on/off toggle, of course.

Worthless to say, if I switch sound output from remote, everything works as expected - both menu setting and actual sound route is changed.

WebOS 5.2.1-2522. HA - latest.

config basic

webostv:
  host: 192.168.1.2
  name: LG TV
  turn_on_action:
    service: wake_on_lan.send_magic_packet
    data:
      mac: xx:xx:xx:xx

Any ideas?

2

Found explanation myself. Somehow (at least my 55BX) cannot switch back to ARC if switched to another output. Nothing with HA nor API - it’s just LG weird HDMI-CEC implementation