The bug is reported here :
My onboard card was recognized as “Generic 14f1 ID 5047”.
root@portable:~# head -5 /proc/asound/card0/codec* Codec: Generic 14f1 ID 5047 Address: 0 Vendor Id: 0x14f15047 Subsystem Id: 0x1179ff31 Revision Id: 0x100000
The volume was low and distorted at 100 % with alsa-drivers 1.0.11
I followed this page http://www.alsa-project.org/alsa-doc/doc-php/template.php?company=Intel&card=ICH+southbridge+HD-audio+and+modem.&chip=ICH6%2C+ICH6M%2C+ICH7%2C+ESB2&module=hda-intel and upgraded manually to the alsa-drivers version 1.0.13
It fixed the issue.
The chip is now recognized as a “Conexant ID 5047”
root@portable:/# head -5 /proc/asound/card0/codec* Codec: Conexant ID 5047 Address: 0 Vendor Id: 0x14f15047 Subsystem Id: 0x1179ff31 Revision Id: 0x100000