Thank you, I shall give that a try.

I have the same issue since a few weeks now. I have the 4th Gen Beoplay a9 which i bought in february. It doesnt bother me that much right now but im curious if this helps and doesnt harm the warranty?

I’ve had my prize draw A9 mk1 for a few months now and have also occasionally heard those plastic popping noises.

But they are rare and only while they are playing rather loudly.

Some people have said unscrewing the back screws to make them looser helps, but I don't know exactly which ones they mean.

And don't worry about the warranty.  I spent 3 years and countless repairs with B&O. They said they aren't aware of the issue and offered terrible/clueless solutions to help resolve the issue.

You need to loosen all the screws that are underneath the fabric cover. There are screws in the black plastic front. Loosen them all just a bit. Try it! It really solves the issue. 

Interesting.. I had only unscrewed the ones around the outside front, under the cover. I still get a pop every few days. On my particular unit I could wait until it had been playing for a while, without popping, then apply palm pressure to the front and back edges to make the plastic adjust.. and pop. Definitely a design flaw with the screw tension or the materials chosen to rub together. Who knows, maybe making the screws tighter would have also fixed the issue.

can you post a pic?

thx mate!