OK, so calibre sees the sony. The next step is to run calibre in debug mode and see what happens.
Make sure the reader is unplugged. Then Open a command box (start, run, cmd) and type
Code:
calibre-debug -g > caldebug.txt
Plug in the reader and wait until calibre detects it (around 10 or 15 seconds). Quit calibre and post the contents of the caldebug.txt file.