I made a confusion with some informations and I thought that I have a Realtek audio card, but in really I have an Intel 82801FB/FBM/FR/FW/FRW (ICH6 Family) High Definition Audio Controller, so when I installed the Realtek High Definition Audio Codecs it made a mess with the sound-related files, resuming, in the driver's readme it says that by default it mutes every audio channel and you is supposed to use some ALSA or OSS mixer to unmute them, and was in this part I noticed I made this confusion, because I got this trying to unmute the channels:
sudo alsamixer returns: cannot open the mixer: No such file or directory
sudo amixer returns: amixer: Mixer attach default error: No such file or directory
I already reinstalled every alsa realated package and got nothing, changing Sound Preferences settings doesn't work and there isn't any instructions to how to uninstall the Realtek drivers. I know the Realtek drivers changed something related to "sdn" and "hda".
So, how can I fix this problem?