IP Office "Feedback" On Speakerphone When Call Connect

[Gus1972]

IP Office 500v2 R9.X (not in the system right now not sure exact release).

When customer places calls or answers calls via speakerphone, there is a feedback noise. Not an echo, hum or distortion, it like "microphone to a speaker" feedback noise.
The control unit and both combo cards have been replaced. The problem occurs on different lines and the lines change after rebooting. (may occur on lines 1 and 4, after reboot 2 and 3 may experience the issue)

I have adjusted the D>A Gain on lines 1 through 4 to -3 per Avaya knowledge base doc SOLN146019. No change to the problem.

The LEC is AT&T and they are bringing in dialtone on fiber through an Edgemarc 4608t router. I did notice the loop current on all 4 lines from the router read a little low (21 to 23ma read with a multimeter).

The problem occurs on all sets (1408 and 1416) and only when calls connect over speakerphone.
Also, station to station calls via speakerphone do not have this problem.

Any suggestions on where to go from here? Thanks!!

 

[intrigrant]

Also, station to station calls via speakerphone do not have this problem.

That implies it is a analog trunk issue and comes from the provider.
Analog circuits are designed to have some audio feedback and is called "side tone" where a the audio from the microphone is send to the speaker with very low volume.
The idea is that if you talk then you can hear yourself, ifyou are on a call then your ear is covered and the natural audio feedback is blocked so the analog circuit provides this natural feedback by sending your voice back to the speaker.

Said that then the return of the audio back to the speaker is generated in the analog trunk circuit and must be adjusted there, it is not a IP Office problem.

https://en.wikipedia.org/wiki/Sidetone

 

[qtelcom]

This might help SOLN243273, or it's the carrier like intrigrant mentioned,

[URL unfurl="true"]https://support.avaya.com/ext/index?page=content&id=SOLN243273&group=UG_ENTITLED_CUSTOMER[/url]

 

[kwing112000]

are they loop start with caller id? could it be the caller id burst your hearing

Kevin Wing
ACSS Small and Medium Enterprise (SME) Communications
ACS- Implement IP Office
ACA- Implement IP Office
Vive Communications