[Asterisk-Users] iaxy and comfort noise generation / sound quality

[Grant Supp]

Am I correct in assuming the iaxy (S101I) does not support comfort noise 
generation (CNG)? I can tell a difference between a call placed using a 
Grandstream 486 ATA and the iaxy. With the iaxy, when the other party is 
silent, the sound level abruptly cuts off to zero. This is fairly 
annoying and wouldn't be acceptable at a customers' presence. With the 
486, random background noise is still heard, more like a traditional phone.

Does anyone have any suggestions or can recommend an ATA with high sound 
quality? So far I have tested the Grandstream 286/486 (unreliable) and 
Digium iaxy (S101I). I have not been able to find a reliable ATA that 
has high sound quality.

I'm still trying to track down the issue, but it seems I'm having more 
jitter problems with the iaxy than the SIP-based Grandstream ATAs. 
Incoming audio on the iaxy often gets choppy. Has anyone else 
experienced this or have any suggestions? I use the ulaw codec on all 
devices and I don't believe the issue is available bandwidth (problem 
seems to only occur using iaxy.) I have the following jitterbuffer 
settings in iax.conf (Asterisk 1.0.7):

jitterbuffer=yes
dropcount=1

Thank you for your time,
-- 
Grant Supp
I N T H R I V E
gsupp at inthrive.com
http://www.inthrive.com
High Availability Web Hosting