This may sound strange but here I go...
First, do you connect the TSU 9600 directly to the computer or are you using the docking station?
Here's what happened to me recently; I was getting the same error and found that the connection to the docking station was not right. Make sure that the connection is all the way in the docking USB socket. I found that the connection to the TSU 9600 is kind of loose and the one to the docking station is more difficult to plug all the way in with the wire.
If you get the error when connected directly to the computer (not using the docking station) then I may not be able to help.

SYL20