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

                                                  01 July 2021                                        osstest(1)