This page is dedicated to fixing issues with LTSP/ALSA setting the default of the "Headphone Jack Sense' attribute while booting thin-clients. This issue causes some audio chipsets to default to not turning this feature on, which in turn doesn't allow the use of headphones. This is especially bad when you have a lab full of computers, as login/logout sounds come through internal speakers at high volumes, and/or other normal usage scenarios require headphones so lab techs/teachers don't go insane.
Chroot to the ltsp chroot and create a simple script:
sudo chroot /opt/ltsp/i386
vim /etc/init.d/headphonejacksensefix.sh
headphonejacksensefix.sh:
#!/bin/bash
#
# Created MM/DD/YYYY YourNameHere
#
# Fixes headphone-jack-sense bug in some audio chipsets for ltsp clients.
amixer set 'Headphone Jack Sense',0 on
# EOF
Make the script executable, set the script to execute in default runlevels, exit the chroot environment and update the chroot image:
chmod +x /etc/init.d/headphonejacksensefix.sh
update-rc.d headphonejacksensefix.sh defaults 98
exit
sudo ltsp-update-image
Reboot affected thin-clients after this is complete and you should now have the 'Headphone Jack Sense' functionality.
