Hey, you are doing better than I am. I'm using one of those cheapo GPX MP3 players I bought a few years back...mainly because it was only $20 and had an SD card slot so I didn't have to be limited to the internal 128mb.
But my point is that I can plug it into any of my CE handheld's or CE netbook's USB port and wait and wait and wait...and it never does show up. Good thing my Wabook has an SD slot.
Probably in your case, unplugging the device is not releasing/resetting the interrupt...
(I really have no idea what I'm saying, but it does sound good, doesn't it?
)