I have a Cruzer Mini 256MB USB drive that used to work fine under OS 10.2.6. After upgrading to 10.3.1, the drive mounts, is functional for about 20 seconds, and then unmounts with a "Device Removal" error message. The drive works fine on a PC, so I guess it must be a software issue on the Mac. I am using a 12" PB. Any suggestions?