D800 - Can't get sharp images - focus woes

My replacement D800 from Nikon arrived today.
Serial = 6065xxx

Guess what, the camera has the same left AF issue as the previous ones Furthermore it had taken 10 images when I unpacked it. Not a big deal in itself, but could be a returned unit or Nikon tested the camera themselves before shipping it to me.

I'm seriously fed up with this. I've spent 3 months dealing with this issue

I don't want a defective camera, but I don't want to be without one completely....For now I'm thinking: D600 or cash refund.

Any recommendations?

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Best regards
/Jim