Hi! After upgrade program external USB drive does not appear in a mac, or in a virtual winxp until insert the wire twice. This happens with both usb drives.
You could try removing the USB devices from the list of Permanent assignments under Parallels Desktop>Preferences>Devices.
It does not help. When turn on a Mac, USB drive devices unmounted from MacOS by unknown process. After hard disconnect and connect the device is normally connected immediately and i can turn it to WinXP. I suspect that it makes Parallels in MacOS (not in WinXP) and trouble is there.