[asterisk-users] Transcoding

[Mark Michelson]

Guilherme Loch Waltrick Góes wrote:
> I have a server with Asterisk 1.4.21.1 <http://1.4.21.1> and some 
> prompts recorded in GSM format. I have these same prompts in another 
> server with Asterisk 1.4.18, on this server the prompts sound pretty 
> nice, but on the first one they sound pretty choppy. Was there any 
> changes on the transcoding code between this 2 versions ? Any hints ?
> 
> Best Regards, 
> 
> -- 
> Guilherme Loch Góes
> 
> Visite nossa loja virtual: http://www.shopvoip.com.br
> 
> Notícias e Fórum sobre VoIP com software livre: 
> http://www.asteriskexperts.com.br

One important difference between the servers may be the compiler used. We have 
heard reports that using GCC 4.2 or later with optimizations on causes choppy 
audio when using GSM.

Solutions to this include either downgrading your compiler to GCC 4.1 or 
earlier, or selecting DONT_OPTIMIZE in menuselect under compiler options and 
then recompiling Asterisk. I also believe that you can set the optimization 
level for compilation to -O2 in Makefile.rules and have no choppy audio, but I 
cannot confirm this.

Of course, if this server isn't running GCC 4.2, then you can ignore everything 
I've said so far :)

Mark Michelson