Thanks for your reply.
All the pins are correctly wired with A to A etc...
the only difference is the Arri connector is ground to the shell of the connector and the filmgear is not.
I can't see this being a problem as once the connector is attached to the ballast it grounds then.
I understand both the head and ballast have some circuitry in them relating to the CCL. Is there also something happening inside the header cable?