I just read, but a little later, a similar comment and if it can brighten someone I autopsied the beast to find out where the problem was. The result: the circuit board is mounted upside down! The pretty symmetrical housing design makes it possible that kind of factory assembly errors. Yes, it is appalling and probably at the limit of being dangerous. To those who wonder how can I be sure my doing: there is clearly written "Out GND" on the printed circuit next to the terminal on the housing while it says "AC IN" ... I do not always come back, I even made shots where burnt traces attest that the circuit was installed upside down when powering that shattered a component. What do you nowadays nobody is testing factory components. Just under labellings (CE, FCC, UL, etc ...) and a bit more quality would not do any harm.
