Thanks for your reply - I have further localised the problem clicking to only happening in shooting mode ( not playback ) and also only happening with the mode dial set to auto -in any of the other modes ie Av, Ap P etc there is no noise. I don't know if this additional info is helpful at all to suggesting a likely problem ?
If it only happens in shooting mode and in Auto mode, not in playback etc.... then I suppose it has something to do with metering and response, leading to a feedback loop in the camera's internal reactions, thus repeated clicking in only that mode.The metering or sensing in the camera, dictates some readjustment, which affects the metering or sensing so as to produce the opposite readjustment, thus repeated clicking. That's one interpretation.I think it need repair servicing for this sort of thing. If e.g. an optical sensor were physically obscured, it would adjust to that in one direction, then stay that way, not repeatedly try and try again.
If you are using an accessory or detachable lens with this camera - it's just a thought, I haven't researched it - then there might be something you could try.
If the lens assembly were clicking, then you might have a situation where a control sequence was attempted, and either the response / sensor response was not received, or similarly - leading to retries, and repeated clicking.
Is the lens assembly used with this camera compatible? (I haven't even checked as to whether this camera can have an accessory lens attached, or whether it is a 'fixed lens' camera - if this is irrelevant, pardon me, please.) The lens assembly part # ***** model # ***** allow me to judge this.
Also, you could remove the lens assembly, with the camera powered Off, and wipe the contacts on the lens mount, both on the lens assembly and the corresponding ones on the camera body, gently, with a soft (clean, dry) cloth... gently so as not to remove the coating on the contacts! then reassemble lens to camera body, and try again.