[asterisk-users] Polycom 301 questions

Lee Jenkins lee at datatrakpos.com
Thu Apr 12 06:19:04 MST 2007

Stephen Bosch wrote:
> Lee Jenkins wrote:
>> Hi all,
>> I just purchased a Polycom 301 for my home office and I believe I have
>> it setup correctly as I can dial out, receive calls in, etc.  However,
>> I'm having the following issue:
>> When calling a local number over a Zap line, I hear a lot of feed back
>> on the line.  I had a Grandstream configured with the same information
>> before I got the 301 and never had that kind of feedback noise.
> Feedback? As in high-pitched squealing?
> I can't imagine any circumstance under which a SIP phone would even
> allow feedback.
> Maybe you mean echo?
> You might also be talking about sidetone, which is the portion of your
> own voice that the phone pipes back to you so that you can adjust your
> voice accordingly.
> Sidetone can be set in the phone configuration; before you do that,
> though, I need to know what you mean by feedback.

Sorry, should have been more detailed.  It's a sort of background 
humming noise, almost like that if you placed the phone next to a high 
output electric device.  Didn't hear it with Grandstream phone so I 
thought it may be something I can change in Polycom.  Of course, it 
could also be that polycom is better phone, but more apt to pick up 
background noise that

It's only on zap calls.  I'm still playing with rxgain and txgain in 
hopes of resolving this.  Basically, the humming noise increase with volume.


Warm Regards,


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