Comment 59 for bug 381201

Confirming the popping, it occurs less frequently, only when the sound card is activated after having powered down.

Far more annoying though is an extremely high pitched "hissing" sound (for lack of a better word), that starts whenever the card powers down. My father cannot hear it, (he is approaching 55yrs) but the rest of us hear it clearly. It might be static gathering because I don't tend to notice the sound until the computer has run for a few hours.

so far it seems both pop and hiss are fixed by the workarounds, either in /etc/modprobe.d/alsa-base.conf or /etc/pulse/default.pa (as suggested by #50)

Hardware
EeeTop 1602
lspci:
00:1b.0 Audio device: Intel Corporation 82801G (ICH7 Family) High Definition Audio Controller (rev 02)

Software
Fresh Karmic Koala install
uname -a
Linux EeeBuntu 2.6.31-16-generic #53-Ubuntu SMP Tue Dec 8 04:01:29 UTC 2009 i686 GNU/Linux