Hi Louis,
What would be the monitored metric or metrics here?
Are there bugs that prompted filing this tracking bug?

I believe the goal is to monitor input and output latency (from client application to sound being played / recorded), in milliseconds.

I don't think there are any bugs that prompted this, but that there are some upcoming projects that would benefit from knowing accurate USB latency.

ACK

Karl / Samuel - I just wanted to get some more context on this before implementing anything..

We can implement a 'loopback' for USB audio, and measure end-to-end latency from user-space output back to user-space as input, however I'm guessing a good chunk of this will be caused by the USB device itself, so I'm not sure this is a useful metric for you.

If you could provide any details on what you're looking to measure and why that would be really helpful, thanks!

The current audio loopback tests now work over USB, eg when a USB-C -> 3.5mm  adapter with 3.5mm loopback dongle is connected.