Comment # 7 on bug 1226449 from Takashi Iwai

The problem is that there are other services that tune power_save option
dynamically, hence the value you wrote can be overridden at any time later.

Could you check the value in /sys/modules/snd_hda_intel/parameters/power_save
and whether it's still 0 or not if the problem appears?  If it's non-zero, then
it's likely the service changing power_save parameter triggered the problem
again.  If it's kept 0 but the bug appears, it means that the original problem
can be somewhere else.