@MKinOZ , From your description, it seems when the Intune managed device is in Domain Network, the Sonos speaker is failed to find. But in Private network, it is working. If there's any misunderstanding, feel free to let us know.
To clarify our issue, please help to do the following tests:
- In the domain network, find a device which is not enrolled into Intune and check if the Sonos speaker can be found.
- Try to enroll one device without applying the Microsoft Defender for Endpoint Baseline to see if it works on it.
Please try the above tests and if there's any update, feel free to let us know.
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