I had the hotshoe problem with D700. The hotshoe exhibits some odd misfires when communicating with the flash. I experienced frequent unwanted low-power discharges; almost as if the flash were “loose”, even when fully secured. Then I shipped to be repaired at APS spending about $300. At the studio I work, there were 6-7 D700 had the same problems.
Now I use "water guard (WG-AS3)", when I place SB900 on hotshoe of D700 or even D800e.