Even before soldering I sourced a receptacle with 4 legs, to have it extra stable sitting, and carefully soldered the legs with plenty of solder in. It seems that it's the contact between the pins of the USB cable and the pins of the receptacle, not the contact between receptacle and PCB. Guess I switch back to some mini B receptacle (by MOLEX), a step back like this is sad, but this crappy Type-C standard kinda forces me to do this. I'm a windows follower, but I have to admit that Apple connectors are at least of high quality, they can do it, but USB consortium can't. Hm... which brings me to the idea... can't I use an Apple receptacle? Lightning or something?