Based on what you all are describing, I’m certain this is most likely what Philips is doing with the wiring:
This is the only explanation as to why the cable only works when L/R is plugged in properly, but doesn’t work at all when L/R are reversed.
It’s a stupid idea. My guess is that it was their lame attempt at trying to make the cable proprietary.
This would also ensure that the headphone would not work at all for anyone who accidentally or knowingly tried to plug a normal stereo AUX cord into only ONE cup (like the X2).
So I guess their logic does sorta make sense in a stupid kind of way.
Assuming I’m right, this means that ALL 3rd party cables will have to be custom wired for the X3, or at least a cable will have to have the ends cut off and resoldered to be compatible.
I don’t know if or when I’ll ever get the X3, but if I ever do, the first thing I’ll be modding is reconfiguring the female sockets in the earcups themselves to be ‘normal’ (assuming I’m right on the goofy proprietary wiring).