My mother in law's PowerBook (G4? pre-magsafe, at least 5 years old, aluminum or titanium) has a power supply that has to be positioned "just right" in order to supply power. The loose connection seems to be in the vicinity of the 110V plug, not on the low voltage side which sometimes wears out on these. When the power supply is disturbed you can hear a spark and the connector's amber light goes out. Is Apple likely to offer a free replacement for such an old product on the basis that it is a potential hazard? There are no signs of wear or abuse.