I have an Asus Zenbook Ux31A which is about 9 months old. A week ago the q k c and . keys stopped working. If I use an External keyboard they are fine. Bizarre thing is if I run Windows 8 defender they start working again only to stop 5 mins later Its driving me crazy - the Defender 'solution' suggests its a software problem can anyone help me cure it before I dump my beloved zenbook?