Google Assistant volume voice command changes Chromecast volume instead of Onkyo receiver

Configuration Voice Assistant
1

I finally configured my Home Assistant to work with Google Assistant, and have my Onkyo TX-NR686 set up through HA and added to my Google Home devices. Everything appears to work as expected through Google Home voice commands, in the Google Home app, and in the Home Assistant UI except for changing the receiver volume when the source is my Chromecast Ultra. If I’m playing audio from my Chromecast and I ask Google to “change the Onkyo Receiver volume to 50%”, the volume slider for my Chromecast changes to 50% and the receiver’s volume remains the same. On the same input however, if I change the receiver’s volume in the Google Home app or Home Assistant UI, the receiver’s volume is adjusted as I’d expect.

The hopeful goal is consistent volume control throughout, where setting the volume for the Onkyo Receiver changes the value on the receiver itself rather than controlling the volume of the device connected to the active source. Has anyone else had this issue? Any gotchas I might be missing here?

Here are some snippets from my configuration.yaml

# Google Assistant
google_assistant:
    project_id: <project_id>
    service_account: !include SERVICE_ACCOUNT.JSON
    report_state: true
    exposed_domains:
    - media_player
    entity_config:
        media_player.receiver:
            name: Onkyo Receiver
            aliases:
            - Receiver
            - AV Receiver
            - Onkyo

# Onkyo TX-NR686
media_player:
  - platform: onkyo
    host: 192.168.1.201
    name: receiver
    sources:
      tv: 'TV'
      strm-box: 'Chromecast'
      pc: 'PC'
      video3: 'Nintendo Switch'
      network: 'Music Apps'

And from my customize.yaml

media_player.receiver:
    friendly_name: 'Onkyo Receiver'
    icon: "mdi:audio-video"
    source_list:
    - PC
    - TV
    - Chromecast
    - Nintendo Switch
    - Music Apps
media_player.receiver_zone_2:
    friendly_name: 'Onkyo Receiver Zone 2'
    icon: "mdi:audio-video"
    source_list:
    - PC
    - TV
    - Chromecast
    - Nintendo Switch
    - Music Apps
2

I’ve been avoiding home assistant because of how complicated it can get (there’s only so many times I want to tinker with something) but I was wondering if you ever got anywhere with this? I would love to be able to change my Onkyo (TX-NR5100) volume from within the Google home app (I have a Google TV streamer), potentially even being apple to adjust my nest audio and receiver in the same group? But I don’t know if that’s at all feasible… I should add that my Onkyo receiver does have a chromecast audio built into it but it never works, shows up maybe once every few months when I go to stream something and that’s it

Good looking so far dawg

Edit: my receiver actually got an update 4 days ago haha we’ll see if it does anything