It does sound like a tip broke off in the unit. You'll need a new DC-IN board (available at the link below):
http://www.powerbookmedic.com/xcart1/cu ... t=0&page=1
And a new power adapter. (Available at the link below):
http://www.powerbookmedic.com/xcart1/cu ... t=0&page=1
-Bradley
PowerbookMedic.com