Provided by: oss4-base_4.2-build2010-5ubuntu1~16.04.2_amd64 

NAME
osstest - Open Sound System audio self test applet.
DESCRIPTION
The osstest applet is a simple test application that can be used to test functionality of the sound
hardware installed in the system.
osstest performs a playback test for each installed audio device. If there are any "machine detectable"
problems they will be reported. You will first hear an audio sample played on the left speaker, then the
right speaker and finally in stereo on both speakers.
It's user's responsibility to listen if the test sound is audible. If no sound output can be heard the
possible reason is one of the following:
1. An error was reported by osstest. In this case there will usually not be any sound output. The error
needs to be fixed before running osstest again.
2. There is no headphones or speakers connected. Or the connection is not made correctly.
3. The mixer volume level is set to a too low value. By default it should be OK. The mixer level can be
adjusted using the mixer, ossmix and ossxmix utilities distributed with OSS.
4. Some notebooks have nonstandard volume control and/or speaker selection hardware that is not
supported by OSS. It's very likely that OSS doesn't support such vendor specific additions.
If no errors were reported and the test sound was audible it means that OSS and your sound hardware is
functioning correctly. If you still encounter problems with some sound applications the reason is almost
certainly in the application. Check it's configuration or try to use another equivivalent application.
If you are having problems with JDS, KDE and/or Gnome system sounds, you need to make sure that OSS gets
started before the GUI environment. Refer to your operating system's startup procedures.
SAMPLE RATE DRIFT
The osstest utility measures a sample rate drift value after playing back the test sound. Ideally it
should be 0% but in practice there will be an error of few percents. 0% means that the 48000 Hz test file
was played exactly at 48000 Hz sampling rate.
The sample rate measurement is based on the system timer which has limited precision. It's likely that
less than 1% differenc between the nominal and the measured sampling rates are actually caused by an
error in the measurement. For this reason the drift reported by osstest should not be used as any kind
of quality measurement. However if the drift is very large it means that there is something wrong in the
system. The oscillator chip used with the sound chip is broken or the system clock is running at a wrong
speed.
USING OSSTEST MANUALLY
The osstest utility is located in the /usr/bin directory. It can be run manually to test functionality of
OSS and your sound hardware. When invoked without any command line parameters osstest performs the
default test on all devices. However it will skip some of the devices base on the following rules.
• It is possible to test just one of the available audio devices by giving its number on command line
(for example osstest 1). Use the device index numbers reported by "ossinfo -a".
• Use the -l command line option to loop the test infinitely.
• Virtual mixer devices will not be tested. Use the -V command line option to force test of virtual
devices.
• The actual (physical) audio devices will be tested directly (bypassing virtual mixer). If you want to
test playback through vmix then use the -V option.
• Multiple device files related with the same physical device will not be tested. Only the first one
gets tested while the remaining ones will be skipped. At this moment there is no way to force osstest
to test this kind of devices.
• Only stereo devices will be tested. Future versions of osstest will be able to test mono and multi
channel devices too. Also osstest requires that the device supports the 16 bit signed format and 48kHz
sampling rate.
• Send a SIGQUIT (Ctrl-\ on most terminals) to make osstest skip a device.
FILES
/usr/bin/osstest
SEE ALSO
savemixer(1)
AUTHOR
4Front Technologies
09 July 2018 osstest(1)