[Beats Studio Buds+] Painful otoacoustic reverberation in Noise Cancellation and Transparency modes?

I experience a painful reverberation in both earbuds on top of my music whenever Noise Cancellation or Transparency modes are active. This reverberation does not occur when Noise Control is off.

I brought my Beats Studio Buds+ to the Apple Store where they were able to replicate and confirm the issue, but when it was sent out to their central repair facility it was returned as "could not replicate."

At this point the effect is immediate and reliable as soon as Noise Cancellation or Transparency modes are active, but I did not have his problem initially (and for a while it seemed to stop occurring). I suspect it is more a software issue than a hardware issue though I also do use these earbuds at the gym when working out.

I suspect it is some kind of otoacoustic effect as swallowing my saliva temporarily relieves the reverberation.

Has anyone else experienced this & if so any tips for fixes would be appreciated! I also suspect that this is just a QA issue with the Beats vs. AirPods.