Sometimes the mere act of unplugging something and plugging it back together can cause the male and femail parts of the connection to rub together and clean off some crud making for an improved connection. It is also possible that in some cases the plug and socket arrangement is not fully snapped together or that the pins may not have been ideally terminated or ideally seated in the multiplug... There are more than enough in the way of variables to provide confusion and frustration, but with a bit of determination you have got there... For now..
