The data seems to suggest it is a firmware problem.
My thought, and hope, as well.
If this turns out to be hardware related there is absolutely no way Nikon is going to fix it. That is, if this problem exists in every V3. That is at this moment unclear. Sofar nobody has come back and told me clearly that their V3 can set small apertures at 10fps and 20 fps.
However, if my camera was one of the early ones manufactured and Nikon discovered the problem and fixed it on later models there is still hope. There might be spare parts that can be used.
I don't know much about manufacturing of high tech electronics but I assume that this kind of thing is not possible to buy at your nearest Radio Shack. These are highly specialized boards manufactured to exact specifications in limited numbers. And we all know what happened to DL...
Thanks to all of you for your interest in my problem!
I just sent a message, one more of many, to Nikon Support reporting the confirmation I got here plus one confirmation I got from a Facebook group (Nikon 1 Enthusiasts).
I will keep you posted about this.
/Johan