I was on the phone with Nick for a couple hours a few nights ago, with a somewhat related problem. For some reason the hardware is not disconnecting when I close the MDX software. I have to either unplug and replug the FB, or disable and then re-enable it in device manager. It will not reconnect and work unless I do this. He was working on finding out why, and had me test about 10 different builds, and was not able to find the problem the other night, as it was getting pretty late.
I wonder if this is somehow related to the problem you are having in some way?