Difference between revisions of "Sound troubleshooting"
imported>ThorstenStaerk |
imported>ThorstenStaerk |
||
| Line 1: | Line 1: | ||
So you want your Linux system to play sound, but it does not? Follow these steps to analyze and solve the problem: | So you want your Linux system to play sound, but it does not? Follow these steps to analyze and solve the problem: | ||
| − | = If your cables and volume are okay = | + | = The Methodology = |
| + | |||
| + | == If your cables and volume are okay == | ||
* make sure your system "sees" a sound device: | * make sure your system "sees" a sound device: | ||
ls /dev/dsp* | ls /dev/dsp* | ||
| Line 13: | Line 15: | ||
The first command throws random bytes into the sound device, the second one uses the "y" byte. The "y" sound is more pleasant to the ears, but with other soundcards than mine, it might not even be audible. | The first command throws random bytes into the sound device, the second one uses the "y" byte. The "y" sound is more pleasant to the ears, but with other soundcards than mine, it might not even be audible. | ||
| − | == If you hear a sound == | + | === If you hear a sound === |
If you hear a sound, your cables and drivers are okay. | If you hear a sound, your cables and drivers are okay. | ||
| − | == If you do not hear a sound == | + | === If you do not hear a sound === |
If you do not hear a sound, see if you get an error message. | If you do not hear a sound, see if you get an error message. | ||
| − | === If you do not get an error message === | + | ==== If you do not get an error message ==== |
If you do not get an error message, it can be a driver issue. To find out, delete all sound devices and re-create them: | If you do not get an error message, it can be a driver issue. To find out, delete all sound devices and re-create them: | ||
tweedleburg:~ # rm /dev/dsp* | tweedleburg:~ # rm /dev/dsp* | ||
| Line 25: | Line 27: | ||
Check again with dd if=/dev/urandom of=/dev/dsp. If you still do neither get an error message nor sound, it is most probably a driver issue. Get yourself a USB soundcard and proceed. | Check again with dd if=/dev/urandom of=/dev/dsp. If you still do neither get an error message nor sound, it is most probably a driver issue. Get yourself a USB soundcard and proceed. | ||
| − | === If you get an error message === | + | ==== If you get an error message ==== |
If you get an error message like this: | If you get an error message like this: | ||
tweedleburg:~ # dd if=/dev/urandom of=/dev/dsp | tweedleburg:~ # dd if=/dev/urandom of=/dev/dsp | ||
| Line 39: | Line 41: | ||
/dev/dsp points to /dev/dsp2, so the soundcard you are using is blocked by mplayer. So, kill mplayer if you are sure that is what you want: | /dev/dsp points to /dev/dsp2, so the soundcard you are using is blocked by mplayer. So, kill mplayer if you are sure that is what you want: | ||
killall mplayer | killall mplayer | ||
| + | |||
| + | = Knoppix = | ||
| + | When there is no sound under Knoppix try | ||
| + | /etc/init.d/alsa-utils start | ||
Revision as of 12:09, 22 February 2013
So you want your Linux system to play sound, but it does not? Follow these steps to analyze and solve the problem:
Contents
The Methodology
If your cables and volume are okay
- make sure your system "sees" a sound device:
ls /dev/dsp*
must list a sound card device file, e.g. /dev/dsp or /dev/dsp1.
- Test if your sound card driver and cables are okay
dd if=/dev/urandom of=/dev/dsp
or
while true; do yes; done | dd of=/dev/dsp
The first command throws random bytes into the sound device, the second one uses the "y" byte. The "y" sound is more pleasant to the ears, but with other soundcards than mine, it might not even be audible.
If you hear a sound
If you hear a sound, your cables and drivers are okay.
If you do not hear a sound
If you do not hear a sound, see if you get an error message.
If you do not get an error message
If you do not get an error message, it can be a driver issue. To find out, delete all sound devices and re-create them:
tweedleburg:~ # rm /dev/dsp* tweedleburg:~ # udevtrigger
Check again with dd if=/dev/urandom of=/dev/dsp. If you still do neither get an error message nor sound, it is most probably a driver issue. Get yourself a USB soundcard and proceed.
If you get an error message
If you get an error message like this:
tweedleburg:~ # dd if=/dev/urandom of=/dev/dsp dd: opening `/dev/dsp': Device or resource busy
You should find out what process blocks your sound card. Do this with the command lsof (list open files):
tweedleburg:~ # lsof | grep dsp mplayer 18251 root 4w CHR 14,35 14320 /dev/dsp2
You see, mplayer is blocking /dev/dsp2, you third soundcard. Now find out what soundcard you are using:
tweedleburg:~ # ll /dev/dsp* lrwxrwxrwx 1 root root 9 Jun 21 10:38 /dev/dsp -> /dev/dsp2 crw-rw---- 1 root audio 14, 19 Jun 21 10:36 /dev/dsp1 crw-rw---- 1 root audio 14, 35 Jun 21 10:36 /dev/dsp2
/dev/dsp points to /dev/dsp2, so the soundcard you are using is blocked by mplayer. So, kill mplayer if you are sure that is what you want:
killall mplayer
Knoppix
When there is no sound under Knoppix try
/etc/init.d/alsa-utils start
