Problem with microphone

hi all,
just joined the site,and hope someone can put some lite on my problem,I was taking to my brother on skye
and everything was ok as I speak to him most nights with no problems using my headphones and mike, but last night all of a sudden I got alot of crackling and the headphones and mike stopped working,and had to go back to typing,,,,Im running windows vista home edition,and using realtek intrigated,,I have tried everything going into the sound section checking for any ticks been taking out or the sound being muted,,,nothing it tells me all is fine,,but it,s not,,I allso tried another set of headphones but still the same,,,so tried a system restore, took it back a couple of days managed to get the headphones working but not the mike, still getting crakling,,,can anyone help on this problem,,or is it a repair job,,like a new sound card,,,I have a fujitsu siemans laptop dual processor....await your
reply,,,thanks alot in advance