Keyboard problem in Vostro 1540

I'm getting random characters while typing and here also it is difficult to type, these happens some time but I'm suspecting it's some hardware problem due to Electrostatic discharge. I don't have hope, it exactly recovers to normal when I replace with new keyboard. Any one please confirm technically? At last the operating can't bear these effects it turns off abruptly! This made me in trouble on important work.

Operating system: Linux (Ubuntu 12.04 distribution)