the male end of the cable broke away after only a few weeks of use. The extension became unusable (unless handyman) .... So yes, the cable was not necessarily great Treaty, connected to a smartphone in the pocket, the tip was probably twisted / pulled, but would not give in.
In short, if you want to use the cable in a "stable" environment (at home, between PC-speaker extension for example), no problem. By cons, if like me is to lengthen a little short headphone cable to plug into naked smartphone or music player, do not Take.