asterisk users - Jan 2006 - IAX voice distortion with full upload channel /SIP ok

On Samstag, 14. Januar 2006 1:47 tim panton wrote:

> That is weird, you would expect IAX to do better than SIP (bandwidth
> wise) 
My point exactly.
> 1) are you sure IAX trunking is actually happening ?
It shows (T) in iax2 show so I am pretty sure. Timestamps are enabled as well.
> 2) what codecs are you using. Are the codecs the same for IAX as
> for sip?
G.711 alaw and yes the same for IAX and SIP.
> 3) is it possible that some of the network hardware is 'sip aware'
I strongly doubt it. Our firewall is but only regarding to opening the correct
RTP ports for a SIP call. No traffic shaping is done on that end.
> 4) How many simultaneous calls are you running between the 2
> endpoints? 
Happens with one call.
> 5) What happens if you turn trunking off ?
No change.

Kind regards,
  JP

On Saturday, January 14, 2006 2:45 PM Rich Adamson wrote:
> The iax problems tend to be oriented around version issues. Many of
> the itsp's have added whatever functionality they needed to asterisk
> to support their operation, and upgrading their code to the latest
> levels is not a trevial task.   
Misunderstanding: I am talking about my private * against our company *. Both
are running the exact same version of Asterisk.
> Given the changes that have occurred in the iax code over the last
> year or so, mismatches in iax versions are known to cause significant
> audio quality issues. Turning off the jitterbuffer, trunk=no, etc, is
> oftentimes the only way to get close to reasonable audio quality.   
I already tried this and this is not helping.

Regards,
  JP