Originally posted by jmmijo
I would carefully remove the chip, but only if it's socketed and check for bent/broken pins and dust in between the pins to make sure. Also note that sometimes the pins will have what looks like a white film on them, this is called oxidation, basically it's corrosion and I found you can use a pencil erasor to carefully clean the oxidation from the pins. Be careful not to bend or break them however.
Thanks jmmijo. I removed the chip (is socketed) and there aren't bent/broken pins. But after inserting it again the sound isn't fixed. I'll try the eraser trick because I remember that some pins have the white film (I used alcohol to clean them)
//edit: Still no luck