[Ubuntu] Fix volume reset after reboot

A small but annoying bug in Ubuntu causes the sound volume to be unmuted and reset to 100% after a reboot or logout.

This can be fixed by editing the /etc/pulse/default.pa configuration file for PulseAudio:

gksu gedit /etc/pulse/default.pa

Then look for these lines:

### Automatically restore the volume of streams and devices
load-module module-device-restore
load-module module-stream-restore
load-module module-card-restore

and comment out the first one:

### Automatically restore the volume of streams and devices
#load-module module-device-restore
load-module module-stream-restore
load-module module-card-restore

Save, logout or reboot and you're set.