core: Google Cast integration, entities for speaker pair or its component speakers in state Unknown when playing

The problem

I have two Google Home Mini speakers configured as a speaker pair. In Home Assistant I have entities for both the individual speakers, as well as the pair. When they are idle, their state is ‘off’ as expected.

In some scenarios, the individual speakers and sometimes also the speaker pair entity have the state ‘Unknown’ instead of ‘Playing’ when streaming music to them via Spotify.

Scenario 1: Play music to a Speaker Group where Speaker Pair is included Outcome 1: Speaker pair as well as both speakers show as state ‘Unknown’

Scenario 2: Play music to the Speaker Pair Outcome 2: Speaker Pair is in state ‘Playing’, and the individual speaker entities show as state ‘Unknown’

Environment

• Home Assistant Core release with the issue: 0.115.6
• Last working Home Assistant Core release (if known): N/A - issue seen with previous versions
• Operating environment (OS/Container/Supervised/Core): HassOS 3.13
• Integration causing this issue: Google Cast
• Link to integration documentation on our website: https://www.home-assistant.io/integrations/cast/

Problem-relevant configuration.yaml

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Traceback/Error logs

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Additional information

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