[Asterisk-Users] Re: Polycom sound quality problems

[Noah Miller]

Hi Eric -

>>> I'm having a problem with my Polycom phones and hoping someone else
>>> has experienced the same thing: Outbound calls are fine, and inbound
>>> calls originating from another SIP phone are fine, but inbound calls
>>> to the Polycom phone from an IAX channel sound like you're talking to
>>> a robot.  The person on the Polycom sounds fine to the person on the
>>> IAX channel, however.  Inbound calls to our soft phones sound just 
>>> fine.
>>>
>>> Asterisk 1.0.5 on Debian (also had the problem with 1.0 on Fedora)
>>> Polycom SoundPoint IP500 SIP
>>> Sixtel is the IAX provider.
>>
>> Check to see what codec is being used for the call.
>> Sean
>>
> Default is U-law, but I also switched it to A-law with the exact same
> results.

I might check out QoS.  You can specify TOS tagging on your IAX 
channels in iax.conf, and the Polycom phones are able to respond to TOS 
tagging (in ipmid.cfg - or in the web interface under "Core Conf").  
Maybe they are are trying to do two mutually exclusive kinds of TOS 
tagging?  You can tell the Polycom phone to just not respond to TOS.

- Noah