No sound - No record is an inherent feature of WASAPI …
“Windows WASAPI host only records loopback when there is an active signal present. When there is no active signal, recording pauses and will restart once an active signal resumes”.
There are workarounds to stop WASAPI pausing , e.g.
In the Windows Sound control panel, just enable “Listen to this device” for any recording device that you are not using. Ensure that the device is muted (recording level set to zero). You now have a permanent, silent playback stream.