I will try but wouldn't be until tomorrow, reading again my explanation is indeed rubbish.
Basically the two wires that come together by plugging connectors into the back of each other before going into the batteries (for both +ive and -ive), these contacts aren't good hence it drops out. So I cut off the standard connectors to bare wires and soldered them both into the back of the same (new) 'corally' male, this then plugs directly into the cells.
I'm not sure this explanation is much better than the first to be honest.
