Hi, I'm developing firmware for a USB audio device for which audio playback currently cuts off after about a second.
The normal system logs via Console do not seem to throw any error related to USB audio (and nor do kernel-only logs via log stream --process 0).
Is there a good way to dive deeper into what might be happening?
Looking into the AppleUSBAudio driver, it contains a bunch of verbose "USB Sound assertion (%s) in %s at line %d\n" logs via IOLog(). Are they supposed to end up in the system logs under normal conditions, or does this require setting IOKit debug verbosity in boot-args?
New to debugging Mac OS kernel things.. thanks for helping!
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tjclement
Add a CommentSo it turns out that this particular issue was a silicon bug in the used NXP microcontroller (erratum ERR050101 - USB endpoint conflict) that caused its USB peripheral to lock up if any other USB device on a hub uses the same endpoint number as an isochronous endpoint on the microcontroller. Plugging the device directly into a host port fixed it immediately.
However, it would still be great to know how to debug AppleUSBAudio for future reference..!