I have a 1 year old rMBP. Something I just learned on a recent trip is that my Garmin GPS478 will not connect "completely" to my MB. When connecting the GPS via USB to the MB I get a GPS message that the USB is connected. Sometimes I get the splash screen asking whether to connect the USB device to OS or Win7 Using Basecamp, the GPS is not recognized, so no up or downloading. What I found through google searching is apparently the GPS is a USB 2 only and cannot communicate with 3.0 Garmin no longer supports this excellent GPS unit. By chance, I plugged in the GPS to the USB connector on the monitor (Apple 27' ThunderBolt monitor) And it works. GPS up and download as normal. The google search suggested trying a USB dock. I tried a couple I have around the house to no avail. The Apple geeks told me the TB monitor is 3.0, but according to the apple website it is indeed 2.0 Anyone run into an issue like this? Any suggestions for a hub that is portable? Do you know if using a USB hub, does it have to be "powered"? Note, I have used this GPS on at least a half dozen Win PC's, both desktops and laptops with no connection issues.