Assuming your Roon Server is installed on the laptop in question: Roon needs a working Roon Server instance running. Closing a laptop lid usually sends the machine into standby, so no software is still running. Please don’t close the lid or disable standby when you do so. See also:
Closing the lid will shut off the network interface; some operating systems will allow you to limit hibernation settings selectively, but on MacOS you’ll need to rely on a third-party app like Amphetamine for Mac to keep the operating system awake.
Long-term, a headless server with a reliable ethernet connection will function best as a Roon Server machine.
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