Took deliver on a second D800 and have configured it exactly the same as my first unit. Both cameras lock up when shooting in BKT mode using either CL or CH shooting options. Cameras work fine with a wired trigger. I carefully compared all menu settings on both cameras and are exactly the same. Firmware updates are current. There is a problem here. When I hold the remote button down in CL or CH mode, at the end of the series, all the remote trigger LEDs are on and the camera is non-responsive. Pressing the on-off button on the remote trigger twice powers off the remote unit and returns the camera to normal operation.