Hello everyone. I broke that %#*@ hinge twice, and repaired it twice. Than a week ago my gf broke BOTH hinges at once. And I gave up.
These earphones’ mechanical design is a total crap. I believe Sony made this poor cheap design intentionally because any amateur on a glance could tell you it’s not going to survive for a long time. Tiny plastic swivel part either wears out to its death in a couple of years just because this Universe invented friction thing, like my 1st time it broke: I walked on the street and suddenly…, or breaks if you just look on these headphones too strictly: 30cm fall for them is deadly dangerous.
How I fixed: I disassembled ear (took off earpad and removed all the screws I see), soldered out two wires of speaker (be accurate, they’re very short). Than I removed all the screws in headrest slide mechanism, fully retracted it and removed. Each ear hinge has a wire inside. To remove it you’ll need to solder out all 7 (or 9, I don’t remember) tiny wires from headphones’ PCB and put away one long elastic cap, and two more tiny ones. Than you’ll need to carefully remove this wire using these holes and some sort of hard but dull pin. After it you’ll have access to the Hinge.
I had this hinge’s head broken. First time I built it up using super glue (cyanoacrylate) with soda: this high-tech is widely covered in Internet. I made some sort of tiny mold out of plasticine and layered it several times with glue-soda-glue-soda. Having enough I let it cure for a while and then processed it with sandpaper and fine file to make a proper form, and finally drilled a hole for a wire in the center of it. Assembled in reverse, soldered. It worked perfectly for a year.
After it broke the second time, I bought spare part on Avito (our eBay clone): https://www.avito.ru/moskva/audio_i_vide... , 1500 RUB (~25 USD w/o delivery) and replaced it instead of repairing, with the same procedure of assembly.
Sorry for my English being far from perfect. I hope I helped someone to fix that osteoporosis guy, finally sell them on eBay and buy some more decent product.