Ah yes, my mistake. Looking at the illustration of the rear sockets on the unit it is No 1 in the black plug which is empty. So this is the phone mute & not required but l do have a CD changer though there is nowhere now for pin 7 to connect to so assuming that the big top socket is the CD connection, l should be ready for a plug and play conversion as per RayKay's advice. Thanks for both inputs, no pun intended.
