I'm not 100% sure of how the D800 goes together, but I think that all of these would be explained by a mirror that is *slightly* loose on one side. The reason that LiveView might fix it is that it causes the mirror to flip up and down, and if my guess is correct, that apparently causes the mirror to seat properly. If this is the case, I think that just releasing the shutter would have the same effect. To put this in perspective, I'd give my guess about a 15% chance of being correct, but I can't think of anything else that would be more likely.
_____ Brian... a bicoastal Nikonian and Team Member
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