Reply to New Macbook Pro not seeing VCI-400 soundcard

I just bought a new (used, 5 months old) Macbook Pro today (Intel i7 2.5Ghz, 8gb Ram) so my girlfriend could use my older one (Intel i5 2.4Ghz, 4gb Ram). The new machine is not seeing the VCI-400. I plug it back into the older macbook and it pops up right away in the Audio Settings, same cable. The ports are working fine when I plug my Iphone into them so I highly doubt its a problem with the port itself. I also tried plugging in my old VCI-100 to check the port and indeed Traktor shows that its receiving MIDI activity from the VCI-100 but NOT from the VCI-400 at all. It seems to be something specifically between the new machine and the VCI-400. Both systems are running the latest version of OSX Lion. Any ideas please?