If whatever is blocking it will break up then use a pin or really small screw driver to break it up then use hoover or a staw to suck blockage out. but dont push whatever tool you use in too far or you will damage the socket (also make sure computer is unplugged when you try this just to be on the safe side).
chris
August 2007
first of all what's blocking it i.e chewing gum maybe ?
also you say computer is it laptop or pc
if pc then it will be easier to go and buy a cheapy sound card if laptop then you are in trouble.
but this all depends on whats stuck in the speaker socket
let me know more about it