What does Zoom (the software) do to USB audio that the teensy doesn't like?

[Caffeine]

I have a teensy (4) using the rev D audio shield, and it works perfectly with my windows 10 PC running spotify etc.

However, today i joined a zoom meeting and about 30 seconds later my audio stopped. The teensy was still accepting button inputs, and the USB volume was being read correctly, but the audio stopped (I have an FFT1024 running a spectrum analyser on a small OLED, and it shows changes to volume, but the spectrum analyser stopped responding too)

i unplugged and re-plugged USB, and it worked fine for another 30 seconds or so, and then the same symptoms.

I changed the zoom meting to use a different audio output, and it worked fine in that I could hear the zoom call, but the teensy audio stopped again after approximately 30 seconds.

After the meeting, I closed zoom, and the audio has been running flawlessly since then.

Any thoughts on what zoom could be doing to the USB audio stream?

 

[Caffeine]

After a bit more experimentation:

Zoom kills the audio on my teensy within a few seconds of starting the meeting. Microsoft Teams also does the same thing, but only on my work (lenovo, Win 10 1909) laptop.

On my desktop (HP, Win 10 20H2) I have not yet experienced the same issues.

I've tried toggling the option to give apps exclusive access to the device, with no help. I've also turned off 'focus assist', also to no avail.

I've also tried the CrashReport function, but it never fires because the teensy doesn't crash.

It's a pain to debug as I can't get platformio/arduino/teensyduino installed on my work laptop.

Is there something I can display on the teensy to see what's going on? Can I access internal state information or debug information from the audio library?