how has it malfunctioned? i had quite a bit of luck with my old abused K141 mk2 reviving them by re-soldering the wires going to the speakers that constantly break (5th time i have to do so in about 10 years of ownership), so maybe not a total loss.
(the K141 speakers can move in relation to the cup, fatiguing the copper until it fails, if yours have a similar design maybe try the soldering iron)
It's like the pressure problem you get with closed in-ears overlaid with low volume so it's just about usable sitting still with balance set to 90% left and volume turned up.
So if you push/pull you can get the pressure right between the driver and eardrum making it listenable, but it's really quiet. How? Who knows. Put them in at work, cycled maybe 3 miles not even in the rain and by the time I got to the train station it had gone. I think it must reduce in volume gradually as I never notice it happening instantly...
The 90% snapped cable that needs resoldering does make speakers quiet but these are
in ears and swapping the left earpiece onto the right cable doesn't fix it so any problem is in the earpiece. I guess the housing must come apart somehow but no idea how and would damage the bit that sits in the ear trying which wouldn't be comfortable, let alone getting it back together without gluing the driver.
I RMA'd the first set and was told it was just a dirty filter, they returned it and it worked for a couple of weeks then same thing happened again so I tried what they suggested to clean it, didn't help, removed the filter (voiding warranty) and no change.
Why always the left, that is the question. And how did they bring it back to life?!
At least reading the last couple of posts made me revisit some of my gear again just now, it's really reminded me of how good modest, but carefully chosen, equipment can be. I'd forgotten how much detail there is in music when it's not coming out of cruddy bluetooth headphones or shopping mall PA systems.
Give me a great recording of music I don't really care for played on a moderately good headphone over my favourite music on a mall PA anyday, there is no contest.
I hope your kids are released soon so you can get back to it.