Mic doens't work! =( Toshiba A300-1ID

Hy people!!

After upgrading win7 to my pc my microphone does not work... at all!
It's quite frustrating since I cannot find any solution to the problem - the truth is that I'm not very good in this issues... =/

Can someone tell me where I can download some driver that actually works for win7 for toshiba A300-1ID? Does someone know how to fix this issue? I would really apreciate some help... =)

Thanks!!

sakura(a)