/usr/share/help/C/ubuntu-help/sound-nosound.page is in ubuntu-docs 14.04.3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 | <page xmlns="http://projectmallard.org/1.0/"
type="topic" style="problem"
id="sound-nosound">
<info>
<link type="guide" xref="sound-broken"/>
<desc>Check that it's not muted, that cables are plugged in properly, and
that the sound card is detected.</desc>
<revision pkgversion="3.4.0" date="2012-02-19" status="outdated"/>
<revision version="13.10" date="2013-10-23" status="review"/>
<credit type="author">
<name>GNOME Documentation Project</name>
<email>gnome-doc-list@gnome.org</email>
</credit>
<include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
</info>
<title>I can't hear any sounds on the computer</title>
<p>If you can't hear any sounds on your computer, for example when you try to
play music, try these troubleshooting steps to see if you can fix the problem.</p>
<section id="mute">
<title>Make sure that the sound is not muted</title>
<p>Click the <gui>sound menu</gui> on the menu bar (it looks like a speaker) and make sure
that the sound is not muted or turned down.</p>
<p>Some laptops have mute switches or keys on their keyboards—try pressing
that key to see if it unmutes the sound.</p>
<p>You should also check that you haven't muted the application that you're
using to play sound (e.g. your music player or movie player). The application
may have a mute or volume button in its main window, so check that. Also, click
the sound menu on the menu bar and choose <gui>Sound Settings</gui>. When the
<gui>Sound</gui> window appears, go to the <gui>Applications</gui> tab and
check that your application is not muted.</p>
</section>
<section id="speakers">
<title>Check that the speakers are turned on and connected properly</title>
<p>If your computer has external speakers, make sure that they are turned on
and that the volume is turned up. Make sure that the speaker cable is securely
plugged into the "output" audio socket on the back of the computer. This socket
is usually light green in color.</p>
<p>Some sound cards are able to switch which socket they use for output (to the
speakers) and input (from a microphone, for instance). The output socket may be
different when running Linux than on Windows or Mac OS. Try connecting the
speaker cable to the different audio sockets on the computer in turn to see if
that works.</p>
<p>A final thing to check is that the audio cable is securely plugged into the
back of the speakers. Some speakers have more than one input too.</p>
</section>
<section id="device">
<title>Check that the right sound device is selected</title>
<p>Some computers have multiple "sound devices" installed. Some of these are
capable of outputting sound and some are not, so you should check that you have
the correct one selected. This might involve some trial-and-error to choose the
right one.</p>
<steps>
<item>
<p>Click the <gui>sound menu</gui> in the <gui>menu bar</gui> and click <gui>Sound Settings</gui>.</p>
</item>
<item>
<p>In the <gui>Sound</gui> window that appears, try selecting a different output from the <gui>Play sound through</gui> list.</p>
</item>
<item>
<p>For the selected device, click <gui>Test Sound</gui>. In the pop-up window, click the
button for each speaker. Each button will speak its position only to the channel
corresponding to that speaker.</p>
</item>
<item>
<p>If that doesn't work, you might want to try doing the same for any other
devices that are listed.</p>
</item>
</steps>
</section>
<section id="hardware-detected">
<title>Check that the sound card was detected properly</title>
<p>Your sound card may not have been detected properly. If this has happened,
your computer will think that it isn't able to play sound. A possible reason
for the card not being detected properly is that the drivers for the card are
not installed.</p>
<steps>
<item>
<p>Go to the <link xref="unity-dash-intro">Dash</link> and open the Terminal.</p>
</item>
<item>
<p>Type <cmd>aplay -l</cmd> and press <key>Enter</key>.</p>
</item>
<item>
<p>A list of devices will be shown. If there are no <gui>playback hardware
devices</gui>, your sound card has not been detected.</p>
</item>
</steps>
<p>If your sound card is not detected, you may need to manually install the
drivers for it. How you do this will depend on the card you have.</p>
<p>You can see what sound card you have by using the <cmd>lspci</cmd> command
in the <app>Terminal</app>. You can get more complete results if you run <cmd>lspci</cmd> as
<link xref="user-admin-explain">superuser</link>; enter <cmd>sudo lspci</cmd>
and type your password. See if an
<em>audio controller</em> or <em>audio device</em> is listed—it should have the
sound card's make and model number. <cmd>sudo lspci -v</cmd> will show a list with
more detailed information.</p>
<p>You may be able to find and install drivers for your card by searching the Internet. Otherwise, you can <link xref="report-ubuntu-bug">file a bug</link>.</p>
<p>If you can't get drivers for your sound card, you might prefer to buy a new
sound card. You can get sound cards that can be installed inside the computer
and external USB sound cards.</p>
</section>
</page>
|