Mystery of the disappearing sound.

The problem.

After installing PCLinuxOS on an Acer 5051AWXMi laptop, the sound would disappear whenever I rebooted the computer.

This was strange behavior, as when ran it from the “Live CD”, it worked perfectly. Furthermore, if I ran the “Advanced Linux Sound Architecture Configurator” in a terminal, (command = alsaconf), the sound would work yet again until the next time I rebooted the machine.

Clearly from the afore mentioned behavior, something wasn't happening during the boot sequence - part 1.

New. After updating the system recently, I lost the sound again. Please see part 2, for the resolution.

The solution - Part 1.

Running alsaconf revealed the driver being used for the built in sound chip (hda-intel).

Inspection of the “modules” (/etc/modules) file revealed the driver was not listed, therefore, not being loaded during the boot sequence.

A simple edit of the modules file to add the driver (just as it appeared in alsaconf – in this case hda-intel) solved the problem.

So a recap to define the steps to take.

1. Run alsaconf to determine the driver to use

#> alsaconf

2. Check your modules file to see if that driver is listed

3. If necessary, add the driver to the modules file via your favorite editing program *

4. Reboot the computer

* Adding the driver simply means using an editing program (I used vim) to type in the name of your driver. So all you need to do is select a fresh line and type the driver name.

For example, my modules file now looks like this:

slamr
martian_dev
hda-intel
nvram
evdev

The solution - Part 2.

If you loose the sound after an update, try the following:

Go back into a Terminal (PC --> System --> Terminals --> Terminal Program - Super User Mode) and add this line to your /etc/modprobe.conf file:

options snd-hda-intel position_fix=1 model=auto

Your file may now look something like this:

As PCLinuxOS is a high-bred system using components from Mandriva and Debian, systems based around the same, may possibly benefit from these fixes.