I've actualy had this problem for while.
When I bought a PSP' awhile ago [Sold it cuz of this problem
] and i pluged in it to a USB port on my computer, everything worked fine.. yadayada.
Then once when i pluged it in, my comp' freezed, i restarted/rebooted my computer and all of my USB and also my memorycards readers stop working' never recognized any devices or cards.
Devices Manager say all ports are working, but its not sold my psp because I couldnt use it with my computer, my digi cam is render useless,scanner ect.
I have a Sony PCV-RS620G....