No necessarily DJ related, unless you Dj with hifi headphones....

My NAD HP50 headphones lost their left channel a while ago. I was feeling a bit sad cos they are 300$ cans, my only closed back hifi ones, and didn't want to trash them.
So out came the solder and I rewired them. Thinking that...well its gotta be wires, right?
After checking them out, my wiring was good all the way up to the transducer. But they still didn't work.
So I emailed NAD trying to source a new driver.
They just sent me one without any questions asked. No 'out of warranty', 'see your local dealer' or 'pay us a packet for cheap spare part'.
I installed. It worked.
Good customer service like that is hard to find.

What I learned from this is.

A cheap rework station is nicer than the dirt-cheapest solder station you can find.
I need a multimeter next.
Headphones that cost more than cheap headphones are still made of the same stuff. Plastic is plastic, screws is screws, foam is foam, speaker driver is speaker driver, cheap internal wiring is ubiquitous. Don't expect magic unicorns in nice sounding stuff.
Nad paid postage on sending something to me from Canada to help me out. I've bought their stuff for 20 years, I probably will continue.