Foreword: it isn't obvious in the context — this cable is to used in the car, hooked up to car amplifier RCA cable, so it's thickness isn't a big deal.
After last time I split cable apart and soldered back together, it lasted a couple of days only if that. So I ordered a new one and opened up old one again. Changed a bit how I do old one and keep brand new two dollar one as a backup.

I know how to solder and all, but with this thing one has to work with sizes as small as a quarter of millimiter. I guess I didn't do a perfect job. It still works, but I have to press on a hacked up bundle of wires, or put it under something heavy enough (eg. map, book) so the it's tight, then it works. Otherwise half of the side doesn't work, i.e. only left or right depending how RCA cable is plugged in.
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