sounds like a damaged usb socket to me.
turn off the pc and unplug it from the mains
make sure none of the metal connectors inside a usb socket is damaged. If it is then make sure no metal pins are touching, and make sure none of them connect to the metal shield - break them off with longnose pliers.
if none are damaged removal all usb devices except keyboard and mouse and try again, then plug each cable in one by one untill issue arrives.
get a powered hub this will help.