Media_player.turn_off doesn't work with google cast built in device?

Configuration
1

Hi, I have a LG soundbar with google assistant built in. It has some bug where the sound is muted when the TV is turned off, which is annoying if you want to then cast some music. So I have the below automation, which unmutes the soundbar when TV is turned off. So far so good. But I also want to put the soundbar to sleep as unmuting wakes it.
Having tested the services, media_player.turn_on sends a cast command (with accompanying ‘bing’ from the device) and media_player.turn_off does nothing. I believe this is because Home Assistant detects the soundbar as a google cast device.

Is there a way to treat this device as a standard media device?

- id: '1614248855928'
  alias: Unmute Soundbar on TV off
  description: ''
  trigger:
  - platform: state
    entity_id: media_player.sony_bravia_tv
    to: 'off'
    for: 00:00:05
  condition: []
  action:
  - service: media_player.volume_mute
    data:
      is_volume_muted: false
    entity_id: media_player.soundbar
  - service: media_player.turn_off
    data: {}
    entity_id: media_player.soundbar
  mode: single
2

I don’t think media_player will turn off the device itself.
Just like when I do turn off on a Google home device it doesn’t shut off the device physically, just the cast.

Will it not go to sleep by itself later?
I believe you need to find a rest command that you can send to it, if it has an API

3

Thanks for the quick response!
For some reason the soundbar’s timeout period is really long and not configurable. Maybe I should time it to see it is really an issue.
Thanks for the API tip, I’ll do some searching.