Summary:ASTERISK-15370: gsm to ulaw transcoding sounds terrible
Reporter:Bob M (manchicken)Labels:
Date Opened:2009-12-26 15:32:21.000-0600Date Closed:2011-06-07 14:08:14
Versions:Frequency of
Description:Playing back GSM files on a ulaw or alaw transport sounds horrible (muffled, noise, cylon sounds, etc).  None of my handsets support GSM, but the default voicemail setup records in wav/wav49/gsm - Under asterisk 1.4 it always played one of the wav's but after upgrading to suddenly voicemails were unintelligible as according to the console it was preferring to play the GSM version and transcode to ulaw.

Tested further by taking any .gsm system sound, renaming it to something unique and using Playback over a ulaw/alaw transport sounds the same (awful).  However, ulaw->gsm sounds fine, using Record() to a gsm file and playing it back over a gsm transport (softphone)


Tested on two different platforms (Intel P3, AMD Athlon) running Ubuntu 8.04 - Asterisk versions,, and all tested and exhibit this issue, all built from scratch from source (NOT packages)
Comments:By: Bob M (manchicken) 2009-12-29 12:04:13.000-0600

Sorry, this bug appears to be the same as https://issues.asterisk.org/view.php?id=11243 - My system is running gcc 4.2 and this is solved by compiling with optimization at -O2 or off.

By: Jason Parker (jparker) 2009-12-29 12:11:57.000-0600

Closing per reporter.