I've tried do undo this but not able to get it disabled. My sound settings need to be redone every boot up as well, but asking that question as well would get neg. feedback.
alsamixer(pictured in original question)
To save settings try
sudo alsactl store (untested)
This fixed my sound problems with Ubuntu 12.10 on a ThinkPad x230
alsa version :
Advanced Linux Sound Architecture Driver Version 1.0.25
For me, the method pertaining to disabling Auto-Mute mode in alsamixer (or gnome-alsamixer) didn't work. So, I dug it deeper and found a similar thread here My headphones mute AlsaMixer when I plug them in, HP DV6 12.04
In my case, I had the problem that plugging headphones in would switch the speaker sound to zero as well as mute it (which is correct and should definitely happen); and when you disconnect the headphones, the headphones would be muted. Moreover, the speaker volume after connecting and disconnecting headphone wasn't getting saved.
What I did was make changes to files in
/usr/share/pulseaudio/alsa-mixer/paths, specifically the files named
Before proceeding, you should take a backup of these files in case anything goes wrong.
analog-output-speaker.conf, I searched for
[Element Headphone] directive and removed
switch = off line, and changed
volume = zero to
volume = merge.
analog-output-headphones.conf, I searched for
[Element Speaker] directive and removed
volume = zero line, while keeping the
switch = mute line.
I couldn't get the
mute-on-activation to work on connection of headphones so that it temporarily mutes the headphones while the 3.5mm jack isn't fully plugged in. I'd update the answer accordingly if anyone comments with a way to do so.
Hope this helps. :)