Summary:ASTERISK-07255: Asterisk Native Sounds ulaw play back with artifacts
Reporter:mustardman (mustardman)Labels:
Date Opened:2006-06-29 11:29:43Date Closed:2011-06-07 14:08:16
Versions:Frequency of
Description:Hi there,

Here is the issue based on my experiments.  Using Asterisk, Zaptel 1.5 on Debian Sarge 2.6 or CentOS 4.3 and replacing the GSM sound files with ulaw sound files produces objectionable artifacts.  Pops, crackes, dropouts etc.  SIP phones are using ulaw as well.  I do not get this problem with Astlinux 0.40 which also uses Asterisk and Zaptel 1.5.

This is 100% reproducible.  Replace the 'vm-password.gsm' with 'vm-password.ulaw'.  Check your voicemail by dialing *98 and then mail.  vm-password.gsm plays smoothly but vm-password.ulaw will have a momentary dropout.  Some ulaw sound files play fine and some have consistent artifacts such as this.

I have also tried using Astlinux 0.40 on the exact same hardware, phones etc. It includes native sounds and also uses Asterisk and Zaptel 1.5.  It does not appear to have this problem.  

I tried installing from scratch Asterisk with Zaptel 1.2.6 and replaced with native sounds.  Same problem as before.  Makes no difference if I am using a Grandstream GXP2000, Aastra 9133i, or Xlite softphone.  All 3 extensions exhibit the same playback artifacts.  All 3 extensions are using ulaw.
Comments:By: Russell Bryant (russell) 2006-07-02 22:30:30

and where did you get these sounds?  If it's a problem with the sounds, and they weren't from the digium ftp site, then there is obviously nothing we can do ...

By: mustardman (mustardman) 2006-07-03 23:00:03


If it's a problem with the ulaw files I would agree there is nothing you can do.  If it's an Asterisk problem with playing ulaw files then it would seem to me that would make it an Asterisk bug or am I missing something?

Seeing as how Astlinux plays the files ok I would assume the ulaw sound files are fine.

By: Russell Bryant (russell) 2006-07-03 23:10:11

Have you tried playing the sound files in question by another application?

By: mustardman (mustardman) 2006-07-03 23:33:16

Plays fine on SOX in WindowsXP.

By: Kevin P. Fleming (kpfleming) 2006-07-13 18:24:47

There is no problem with Asterisk playing ulaw sound files; my systems have played thousands of them in the past year with no trouble.