I have a laptop Pavilion ZE2000. This is important because for year and a half that i have using Ubuntu, the mute button, which has a led, has never worked before. Now, a few days ago, it turned on after an update that required restart and not none of my panel buttons for the volume works and doesn't turns off, I used to be able to turn up or down the volume or mute it even if the led did not turned on. Now, none of them works, the volume control on the screen panel, can be marked as mute and still there is sound. I must open the controls and shut off manually the master control.
On the other hand, sound has become crappy, very low, doesn't improve unless I connect speakers (thing that I don't do unless strictly necessary because of the plug being at front) and sounds as if the embedded speakers were blasted. I know they're not. So, how can I recover my sound configuration? I use Alsa-mixer as the controller of the sound card, an intel 82801DB-ICH4.

Please help! I don't care if the button turns on or not, I rather functionality over looks.