Most engineers can fix any problem they can reproduce. So if you have a scenario you can use to reproduce this issue it can likely be solved. Help the engineers out and document it well. Include things like the specific video you were watching or music you were playing, volume settings, etc. And then run your documented steps and verify you can make it happen. I don't think I have ever seen a problem with a well documented reproduction sequence that could not be solved.
That was all done for them. I've given them the conditions under which is occurs. Steps to reproduce. What fixes it, e.g., killing coreaudiod and rebooting. I've also told them that it only occurs under 44,100 Hz and not 48,00 Hz.
I've provided multiple videos of this occuring with both ways to cure it temporarily and also provided a system diagnostic file for them to review.
That last step was done about an hour ago and I'm now waiting for further advice.
I've also asked that they extend my return period while I keep the laptop here to run their tests that they are requesting of me.