Hi,
The error you encounter is exactly a bad shutter. I had this issu with my D2H, 2 times, and I ask Nikon to replace the shutter mecanism. It took 5 days and actually, my D2h who is 14 yrs old, has is third new shutter and I have 25,463 shots...
I also have a D2Xs in perfect working order, and I use it !!
Denis