this is kind of a winter issue,when the heat is on & the air is dry. you get static shocks when you walk across the carpeting
there are static discharge mats (they used to have them in appliance stores, so if you touched a tv or vcr (i am dating myself)
if you have a carpeted floor, one of those mats is a great investment
there are also UPS's (battery backups) that protect a usb
to answer your question, you can plug different computer in to the usb and see if you get hardware install popup
normally if it is your computer you can just switch to a different usb connector on the pc
if a different computer "sees" the printer, you can use a utility like usb oblivion to clear all usb history on your computer, it makes you reinstall all your usb devices
i have never had a sp300v, does it have another input (network or parallel? )