Toshiba keyboard issue?

My mother has a Toshiba Satellite L455 laptop. In the past few months, her Toshiba Laptop Keyboard has been acting up. Every time I type the t,o,u,e, 1, or 2 buttons, the cursor jumps to the start of the line. It's almost impossible to type anything! I have done a complete system restore but that has not fixed the problem. She insists that nothing has spilled on the Laptop Keyboard. Any ideas or suggestions? How about buying the Dell Laptop Keyboard or Sony Laptop Keyboard?