Before trotting off to college, my Shop Assistant repaired a pair of headphones she’d scrounged at the end of her Senior year; they were nice Skullcandy on-ear phones with one dead cup. The previous owner evidently wasn’t into fixing things and bequeathed them to her.
She dismantled the offending cup to find some really grody soldering that ought to have produced a cold solder joint: the common lead wasn’t making contact with the plug. Alas, the only way to proceed was to slice the injection-molded cover off the plug and see what was inside; to our surprise, everything looked fine.
We then cut an inch off the cable and pulled the conductors out:
Well, that was easy! Here’s a closer look:
The three broken wires (only one of which was completely disconnected) failed exactly at the end of that plug covering. It had strain relief notches, but we guessed the previous owner had no qualms about bending the cable hard against the end of the plug.
She soldered it up, shrank some heat stink tubing around the plug and its sliced cover, wrapped self-vulcanizing tape around the junction for better strain relief, and it’s all good. She’ll get plenty of use out of the headphones in the dorm …