Howto detect an unplug
Basically what worked for me was:
# When plugged in:
cat /proc/asound/card0/codec#0 > pluggedin.txt
# When not plugged in:
cat /proc/asound/card0/codec#0 > notplugged.txt
# Then compare the differences
diff pluggedin.txt notplugged.txt
For me the difference was in 'Node 0x16' under 'Amp-Out vals':
Node 0x16 [Pin Complex] wcaps 0x40058d: Stereo Amp-Out Node 0x16 [PinComplex] wcaps 0x40058d: Stereo Amp-Out
Amp-Out caps: ofs=0x00, nsteps=0x00, stepsize=0x00, mute=1 Amp-Out caps:ofs=0x00, nsteps=0x00, stepsize=0x00, mute=1
Amp-Out vals: [0x80 0x80] | Amp-Out vals: [0x00 0x00]
So I based the detection on the difference found.
With this knowledge you can have a script running in the background. If unplugged the scripts mutes your speakers like using
amixer sset Master playback 0% (or any other command).
# This scripts detecs unplugging headphones.
while [ 1 ]; do
# The following line has to be changed depending on the difference (use diff) in '/proc/asound/card0/code#0'
status=$(grep -A 4 'Node 0x16' '/proc/asound/card0/codec#0' | grep 'Amp-Out vals: \[0x80 0x80\]')
if [ "$status" != "$oldstatus" ]; then
if [ -n "$status" ]; then
echo "Plugged in"
amixer sset Master playback 80% # Set volume to 80%
amixer sset Master playback 0% # Mute
You can make it executable with
chmod +x scriptname.sh and put it in the startup applications. You will have to adjust the unplug detection though by finding your own difference in
/proc/asound/card0/codec#0 (maybe even change the numbers here for multiple soundcards.
How to automatically change volume level when un-/plugging headphones?