I’m a musician and did a lot of live and studio audio work in the past. I’ve most definitely heard said popping, although not sure when it started exactly.
It’s not really apparent if I’m using communications mode where the engine / world sound is on my speakers and comms coming through my headphones. But if I run all my sound through my headphones, I can hear it. I had been using the former setup for some time now since I had been home alone for 6 weeks while my son was away on business. But I started using my headset again last week after he got back and started noticing it.
I’ve ruled out my headset or connections as being the issue since I can’t reproduce this in any other scenario other than MSFS.