What do you mean by doesn't recognise? I *think* that when I first connected the TF to my XP PC it had a little one of those pop-up boxes. Now it doesn't say anything. However if you go into Device Manager -> 'Sound, Video and Game controllers' You should see 'USB Audio Device'. This is the TF.
Maybe you're right. USB devices usually produce a popup when connected to a pc. I remember that it was so when I wired the Timefactor for the first time.
But saturday night I had to make a dump and I didn't "see" the Timefactor as external unit in the tray icon bar. Since MidiOX hasn't been eble to receive the midi data, I thougt it was because the computer didn't recognize the device. After several tests I understood that I had to increment the buffer data and finally I get the dump. As I can I want to check into Device Manager -> 'Sound, Video and Game controllers' to veryfy if it is as you say.