Possibly you have a conflict between PulseAudio and Alsa
Remove all traces of Pulseaudio:
sudo cp /usr/share/alsa/alsa.conf /usr/share/alsa/alsa.conf.bak
Add repositories "gnome-media / applets / settings-daemon" to change the Sound Control Press by "gstreamer-based" (This is ideal for users who want OSS4 in GNOME) with:
sudo apt-add-repository ppa:dtl131/ppa
Install the following packages alsa with the following command:
sudo apt-get install esound esound-clients esound-common alsa-base alsa-tools alsa-utils alsa-oss linux-sound-base python-alsaaudio gnome-media libsdl1.2debian-alsa
Uninstalled pulseaudio the following packages with the following command:
sudo apt-get purge libcanberra-pulse pulseaudio pulseaudio-esound-compat pulseaudio-module-bluetooth pulseaudio-module-gconf pulseaudio-module-udev pulseaudio-module-x11 gstreamer0.10-pulseaudio pulseaudio-utils pavucontrol
reinstall Alsa:
sudo apt-get --purge reinstall linux-sound-base alsa-base alsa-utils linux-image-`uname -r` linux-ubuntu-modules-`uname -r` libasound2
reboot
With this we have eliminated the conflict between the two managers audio, leaving only Alsa.

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EDIT----------------------------------------------------------------------
Maybe you just missing libraries so you can start with:
sudo apt-add-repository ppa:dtl131/ppa
sudo apt-get install esound esound-clients esound-common alsa-base alsa-tools alsa-utils alsa-oss linux-sound-base python-alsaaudio gnome-media libsdl1.2debian-alsa
sudo apt-get --purge reinstall linux-sound-base alsa-base alsa-utils linux-image-`uname -r` linux-ubuntu-modules-`uname -r` libasound2
This not uninstall anything and you make sure you have everything you need to work perfectly with Alsa