I've solved it now. It was the cash box connection. I noticed it was also paying all the cash in one as opposed to three pound at a time. I disconnected one of the wires and it works fine now and is macing me all the time !!
I have probably put 150-200 pound in it since I bought it and it has paid about 400 out.
Its as though it is on freeplay and constantly puts me on the feature board. It lets me go to Super Series almost everytime and gives me Jackpot Repeater.
Would be nice if I was in a pub of course but no good at home.
Was thinking it may be something to do with the door switch.
Does anyone know why my Wipeout machine pays the Jackpot all the time ? Just bought it and got it home. It plays fine but keeps paying the jackpot. I only need put a tenner in it !!!!