Fixed ! USB Connection to 912
From Pocketbook's support..
There is a problem with 2.1.3 firmware.
Downgrade to 2.1.2.
I did this this morning and now the pocketbook is recognised consistently regardless of which laptop, USB port or via a hub.
Do not listen to suggestions which suggest plugging this or that end of the cable first, waiting for the green light to go quiet or a particular phase of the moon.
There are some really disappointing aspects.
* The first reply you get (I got) from support was a canned message blaming my computer/cable/..
* This is a known problem with 2.1.3 firmware, but they are leaving broken software on their site.
* When I bought the pocketbook two weeks ago, there was a note suggesting one should update the firmware. This means pocketbook is distributing advice that they know will break USB connections.