[asterisk-users] Background noise

[Philipp von Klitzing]

Hi!

> i have recently connected my (working) asterisk 1.2 server, with two 
> 1.4 asterisk servers (one using SIP the other using IAX), since then 
> (i believe) people starts complaining about a high background noise

The best idea is probably to start out by looking at the codecs. If you 
happen to have either gsm or g726 somewhere along your media path then I 
would strongly suggest you start to get rid of them so see if that 
eliminates the issue. g726 is one big mess, and gsm had some compiler 
issues in the past.

The next thing to look at is if the issue only appears when IAX is 
involved.

Maybe looking at the Polycom firmware, and release notes in particular 
(no clue how detailed those are), would also be a good idea.

Philipp