Error: RuntimeWarning: coroutine 'ServiceRegistry.async_call' was never awaited

[jshank]

I get a successful setup of the integration but am unable to get any music to play.

Item	Value
Home Assistant Version	core-2021.9.7
Installation Type	Home Assistant Container
Installation Method	HACS
HA's Plex Integration works without issue	True

Command Executed (Developer Tools - Services)

service: plex_assistant.command
data:
  command: Play artist jason mraz

The Google Home device Office Speaker makes the chime sound, nothing is played and the following error shows in the logs.

/config/custom_components/plex_assistant/__init__.py:90: RuntimeWarning: coroutine 'ServiceRegistry.async_call' was never awaited
  hass.services.async_call("plex", "scan_for_clients", blocking=False, limit=30)
RuntimeWarning: Enable tracemalloc to get the object allocation traceback
2021-09-29 15:48:10 DEBUG (SyncWorker_4) [custom_components.plex_assistant.const] Command: Play artist jason mraz
2021-09-29 15:48:10 DEBUG (SyncWorker_4) [custom_components.plex_assistant.const] Processed Command: {'media': 'jason mraz', 'device': 'Office speaker'}
2021-09-29 15:48:10 DEBUG (SyncWorker_4) [custom_components.plex_assistant.const] PA Devices: {'Plex (Plexamp - REDACTED)': {'entity_id': 'media_player.plex_plexamp_REDACTED', 'device_type': 'plex'}, 'Office speaker': {'entity_id': 'media_player.office_speaker', 'device_type': 'cast'}, "Lissy's Lounge": {'entity_id': 'media_player.melissas_office', 'device_type': 'cast'}, 'Bedroom speaker': {'entity_id': 'media_player.bedroom_speaker', 'device_type': 'cast'}, 'Garage': {'entity_id': 'media_player.garage', 'device_type': 'cast'}, 'Front Room speaker': {'entity_id': 'media_player.front_room_speaker', 'device_type': 'cast'}, 'Kitchen Display': {'entity_id': 'media_player.kitchen_display', 'device_type': 'cast'}, 'Living Room TV': {'entity_id': 'media_player.living_room_tv', 'device_type': 'cast'}, 'Onkyo TX-NR676 E759C8': {'entity_id': 'media_player.onkyo_tx_nr676_e759c8', 'device_type': 'cast'}}
2021-09-29 15:48:10 DEBUG (SyncWorker_4) [custom_components.plex_assistant.const] Device: Office speaker
2021-09-29 15:48:10 DEBUG (SyncWorker_4) [custom_components.plex_assistant.const] Media: [<Track:26028:Let's-See-What-the-N>, <Track:26029:Have-It-All>, <Track:26030:More-Than-Friends>, <Track:26031:Unlonely>, <Track:26032:Better-With-You>, <Track:26033:No-Plans>, <Track:26034:Sleeping-to-Dream>, <Track:26035:Making-It-Up>, <Track:26036:Might-as-Well-Dance>, <Track:26037:Love-Is-Still-the-An>, <Track:28601:Look-for-the-Good>, <Track:28602:Make-Love>, <Track:28603:My-Kind>, <Track:28604:Good-Old-Daze>, <Track:28605:You-Do-You>, <Track:28606:Wise-Woman>, <Track:28607:Take-the-Music>, <Track:28608:Time-Out>, <Track:28609:DJ-FM-AM-JJASON>, <Track:28610:Hearing-Double>, <Track:28611:The-Minute-I-Heard-o>]
2021-09-29 15:48:10 ERROR (Thread-13) [homeassistant.components.cast.media_player] Failed to cast media /library/metadata/26028. Please make sure the URL is: Reachable from the cast device and either a publicly resolvable hostname or an IP address
2021-09-29 15:48:10 ERROR (Thread-13) [homeassistant.components.cast.media_player] Failed to cast media /library/metadata/26028. Please make sure the URL is: Reachable from the cast device and either a publicly resolvable hostname or an IP address

[github-actions]

Important:

Issues that don't provide the information requested in the troubleshooting docs may not get a reply and may be closed until the info is provided. Please, include as much of the requested info as possible so that I can replicate and investigate your issue.

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[jshank]

Adding that my GoogleCast devices are on a different VLAN (mDNS discovered) with internet access only. I'm able to use the HA TTS service for audio notifications so I don't think that's the problem.