How to fix Xiaomi In-Ear Headphones

My favorite Xiaomi Piston 3 In-Ear Headphones recently stopped working on one side (or very quiet).
These were my 2nd pair that had failed so I decided to investigate further.

After a bit of googling, I stumbled upon this post:

He removes the rubber tips and then using a pin or tweezers removes the mesh.

This is what is causing the issue.
The mesh has become clogged with ear wax - ewwww.

You can then try to clean the mesh, or as I did remove it completely.

For the last 12 months, my earphones have been running perfectly without the mesh.
I simply remove the tips and clean the earphones every couple of weeks.

So, don't throw them out - just clean or remove the mesh!