Laptop keyboard stopped functioning properly

Basically today out of blue my Laptop Keyboard started acting up. For example I press “s” but I see “`s” on the screen. Some keys don’t work at all.

And the weird thing is it keeps changing, in a sense that for example in the morning I press “s” and I get “`s”, then few hours later “s” works correctly.. but pressing some other key output multiple characters.

Then sometimes it spontaneously will start outputting some character onto any input field that is available as soon as I click on it to gain focus. And it will just keep on going and going, as if I keep a button pressed (which I don’t).

At first I thought this was a virus, but I have a dual boot of Windows 7 and Ubuntu, and I get same problem on both. I even tried to boo live CD, and still had same problem.

Anyone had this kind of problem?

It’s a Toshiba Satellite C665 (Black Matte) Keyboard . It is around year old, but quite well kept. Never spilled anything on it, or dropped it. And my wireless USB keyboard works perfectly on it (appart from the spontaneous character inputs, which I can stop by hitting NUM LOCK key)