Thanks for replies I was hoping for a quick fix.... "Oh its ya thingy thats wotsit" etc. but alas.
The circuit goes on stairs that link upto a loft conversion that was done 15ish years ago methinks.
As for Earth wires not connected on the upstairs switch, its all plastic (box and switch...
2 lights top and bottom of stairs. 2 light switches one at the top other at the bottom.
Problem is the bottom light works fine for awhile then it doesn't. It has kinda flickered, before not working on previous occasions. I've noted the wiring on each switch and as of now (with the bottom light...