Further to my last posting on the Brompton Breaking Spokes Saga,yes another one went in the rear wheel,so back to the LBS.
This time I had the rear wheel completely rebuilt with new spokes and the wheelbuilder put some what look like small brass washers around the spoke holes in the hub as it was said that the holes are too big therefore leading to the spoke moving about more than it should and conseqently wearing prematurely.
I had seen this advice on one of the folding bike forums so we shall see if it improves things.