Brightflash64 - 2017-05-06

Many Skywave Linux users with Dell, Hp, and Compaq hardware have the "no sound" issue. It stems from pulse and alsa not doing a good job of automatically finding and configuring the particular soundcards used on those computers. It is an irritating problem that has existed for years and particularly bothersome on Skywave Linux due to the need to specify sinks and plugins for the audio processing chain.

If you have hardware which does not have functioning sound on initial boot of Skywave Linux, consider doing a persistent USB or full installation where system changes are not lost at shutdown.

Make note of the cards and subdevices on your system. In a terminal, enter the command "aplay -l" without the quotes. Some systems have only one card, 0, while others may have a second card, 1. Subdevices are on those cards, and HDMI audio is output is often the first, or 0, subdevice.

Pulseaudio is configured to use the device "sysdefault" and a chain of processing plugins. If there's an issue with the driver then audio won't run properly on device sysdefault, but there are work arounds. You could edit (as root, sudo gedit) /etc/pulse/default.pa and change the device in line 47 from "device=sysdefault" to "device=hw:0,0" or pethaps "device=hw:0,1" if HDMI is on "hw:0,0".

The snd-hda-intel driver should, but often does not, properly configure sound when the computer is made by one if the previously mentioned manufacturers.   Here is an extensive list of model options for the snd-hda-intel driver. Remove the default driver and insert the driver with a specific model option.

For Dell laptops, try this:

sudo su
modprobe -r snd-hda-intel
modprobe options snd-hda-intel model=dell-m6
alsa force-reload

For many HP machines this works:

sudo su
modprobe -r snd-hda-intel
modprobe options snd-hda-intel model=auto
alsa force-reload

Then bring up the mixer:

alsamixer

In alsamixer, use F6 to select your sound card then set levels. The "m" key mutes / unmutes channels.
"Esc" to exit alsamixer. Then save the mixer settings, switch to user skywave, and start pavucontrol:

alsactl store
su skywave
pavucontrol

In pavucontrol, check the levels again, making sure the speakers or headphone output is unmuted. You should hear sounds doing a speaker test.

speaker-test -t sine

You should hear a tone alternating between the left and right channels.