hi, i have an NU dvd burner and i bought an ac adapter for it, and plugged it into a powered USB hub, and i get an error from windows xp, " one of the usb devices attached to this computer has malfunctioned and windows does not recognize it" . so it wont add the dvd burner to the system. any help GREATLY appreciated as this is the second dvd burner i bought to try to work. the other one doesnt recognize my burned dvds , but recognized the ones i just burned with nero. thanks. derek