Thanks for your help. I've just added the requested trace in FB15238028

OK, I added a ktrace for my driver process in FB15238028. I think it should be easy to reproduce the problem on your side using the app and the additional information I added to this Feedback item.

Thanks for your answer. I already opened a FB item which is FB15238028 and added some more information there.

I have an application which talks to the driver through IOUserClient. So I think I will need a dext and that's why I decided to use building_an_audio_server_plug-in_and_driver_extension as starting point. And so I'm quite sure I need com.apple.developer.driverkit and com.apple.developer.driverkit.userclient-access. Will I be granted these entitlements for a virtual driver? But I don't know why I should need com.apple.developer.driverkit.transport.usb which is also used in this sample.

Thanks for the reply, which confirms my findings. So still my questions are open: would I be given the mentioned entitlements for a virtual driver running as a AudioServerPlugIn? And is Apple thinking about opening the AudioDriverKit also for virtual drivers or is there a technical background which impedes this?