Audio codec consuming high battery power
Solution 1:
Unfortunately this is a know bug as explained in:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/877560
Here you have a few workarounds (cited from the bug comments):
1. Manually force power save for the audio codec
Before proceeding, in a terminal launch the following:
cat /sys/module/snd_hda_intel/parameters/power_save*
if the result is different from:
1
Y
then try the following commands
echo 1 | sudo tee /sys/module/snd_hda_intel/parameters/power_save
echo Y | sudo tee /sys/module/snd_hda_intel/parameters/power_save_controller
pkill pulseaudio
and then log out and log in again to get pulseaudio restarted.
2. Let the silence fall
If you mute your mic and your speakers, the device will be deactivate. It sounds strange, but it actually works for me.
3. Wait for Raring
According to the bug report, the problem is gone with kernel 3.7, and Raring will probably mount kernel 3.8.