Cause of null data in Exclaves audio buffer copyouts (SRD experiment)

Ascertain why audio buffer copyouts via Exclaves APIs returned null bytes during the Security Research Device experiment and identify the correct buffer registration or prerequisites required for successful data flow.

Background

The authors successfully created a sensor and audio buffer and received return ports, but audio data copyout returned all zeros and no indicator light occurred.

Understanding this failure mode would clarify the correct usage of Exclaves buffer APIs and prerequisites for sensor data flow in practice.