Thanks for the replies. I managed to talk to Nikon in the UK this morning and demonstated the noise over the phone. Got the stock "never heard that before" (could well be true I'm just an old cynic).

Recommended I return it for replacement which I have done.

Avisys, interestingly they asked me to fire it with the flash up and down which actually made no difference this time but it looks like they know about that problem.
I'll let you know when my replacement arrives.

Mike

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