We've recently become aware of a fringe case scenario involving the latest update to the Microsoft HoloLens (21h1) and the way it communicates with RemoteSpark.
In rare instances, users are reporting that their calls are failing to go through and failing at the "webcam and mic initialized" stage.
This is caused by a bug in the HoloLens 21h1 update where it disables the microphone and webcam for third party applications.
The solution to the problem is relatively simple.
Navigate to Settings on the HoloLens proper (not within RemoteSpark).
Navigate to Privacy.
Navigate to Microphone and ensure that it is toggled On for RemoteSpark Client.
Navigate to Camera and ensure that it is toggled On for RemoteSpark Client.
After completing these steps you should be able to successfully initiate a RemoteSpark call from your HoloLens.
Please note: you need to follow this order precisely. If you don't toggle on the microphone first you won't see RemoteSpark as an option under camera.