The alsa guide contains the lines: # cat /dev/urandom > /dev/dsp Note: /dev/dsp is a symlink to /dev/sound/dsp and should be automatically created. Try re-directing the output to /dev/sound/dsp in case you don't get a "No such file or directory" error. The fact that you would get a "No such file or directory" error is wrong. If you run the command as a user and /dev/dsp does not exist, you will get Permission Denied. Worse, if you run it as root (as the '#' prompt suggests), the file will be created and it will probably contain megabytes of random before you get a chance to press ^C. I think the guide should point this out.
After considering the consequences of the command as well as other saner ways to test, I've removed the section from the guide entirely. In the long run, I'm sure we'll have lesser problems that way. Thank you for you valuable input and apologies for taking so much time to fix this.