Recent changes to ALSA for power saving

[Daniel Chen]

Hi all,

Luke and I have just pushed a one-line change to 9.10's
/etc/modprobe.d/alsa-base.conf that enables HDA controllers to power
down their amps after ten idle seconds. This change anticipates the
larger power-savings objectives for 9.10.

We expect there will be regressions in the form of audible pops when
the AMPs power down (and/or up). If you experience this symptom in
9.10, please file a bug using "ubuntu-bug alsa-base". Be sure to
change the summary of the bug afterward to "[9.10 regression] HDA
power_save=10".

Thanks,
Dan