Travel Technology - Slightly OT: Laptop USB problems

I have a Sony Vaio v505ax laptop, which has been great for travel. However, though its specs say that it has USB 2.0 ports, they only run at USB 1.1 speeds. I'm running XP Pro XP2, and have updated all drviers, but it doesn't help. I even tried re-installing SP2. I've got a PCMCIA USB port which the laptop recognizes without additional drivers, and it runs just fine and at 2.0 speeds. I've run out of things to try.

Does anyone have any suggestions?