"Wouldn't that explain why some people have a connector which is wired back to front?

BTW I agree, the pic you showed has the connector soldered the wrong way round!
Don't you just love Chinese quality control...."

"I still don't know what blows the regulators but for information I have changed the blown TPS79133 TWICE (or two times for our American cousins) and both the new and tested regs blew again with nothing other that a USB cable to the board.
In the end…"

"I can confirm that removing the blown 3.3v reg and replacing it with a78L33 works very well!"