It is possible that it needs a master reset, which Whites gives over the phone. I send a V3i in once before warranty expired for a good checkup...actually I wasn't happy with it right then anyway. It came back and seemed solid for the first 20-30 minutes in my yard when playing with it, then it got all wonky and unstable. This was within the first 20-30 mins remember, so I called up Whites and got Mary to walk me through the MR procedure. My point is, even a newly revamped and certified machine can get the spooks in it for some reason. My V3i did settle down after the MR.
I actually wasn't aware that the VX3 could be upgraded to a V3i until your post. martin