Right guys I have sorted the problem, after looking at the wiring again and finding a old ISO cable from my brothers head unit I tried that and had the same problem. I then connected it all back up and it works! Saves stations and setting when face and ignition are off. As I was slotting the head unit back with the ignition on it then kept cutting out and coming back on which made me look at the actual connections, and what do you know the ISO cables red wire when wobbled breaks the connect. So I removed it and added some heat shrink around it to bulk up the connection and re applied it meaning it now doesn't moved. now the connect is fine meaning the head unit works perfectly.

James