Hi sorry for the late reply, for some reason I've received no notification emails.
Anyway the lights are 30w led tamlite, and 3 out of 9 failed.
I've used ip66 boxes to connect the flex from the lights and also the next light down ect..
I've used sy 3 core because it's cheaper that swa and I've used it before for outdoor lighting with no problem.
I discovered that water had been retained in the cable from when the box flooded and this somehow rusted the strip connector in the first box.
I have changed the 3 lights, and about 20 metres of cable, sealed all screw and cable entries with Sealent , tests came back fine dead and live.
No there wasn't any water ingress in any of the lights, I checked (was hopeing there were on grounds of returning them)
The stuffing glands used were just white plastic ones which I also have sealed inside and out.
When you mentioned the driver has gone what did you mean? Sorry if it seems a stupid question?