Conferencing Problem

[cms18]

I’m having a problem with conference calls on our IP Office. Once a third person is added to a conference through a telephone on the system, the line ends up getting heavy distortion on it. The distortion is to the point where you can’t hear any of the other people in the conference. Our switch is an:

IP Office 412, Release 3.0 with 5 Digital 30s, 1 Analog Trunk 16, and 1 Phone 30
4412D+ phones
PRI and T1 feeding the system

This is happening internally as well as on outside calls, so that rules out problems with the PRI and T1. The system is grounded. Rebooting the system doesn’t change anything either. I’ve had two Avaya engineers out so far and they can’t figure out what’s going on. I also have another similar setup, but an IP Office 403 instead, and conferencing is working fine on this system.

Has anyone come across this problem or have a suggestion on something I’m missing?

 

[IPGuru]

Have the Avaya engineers tried replaceing the IP412 yet, it could be something as simple as a hardware failure.

 

[nathanbland]

I have had a similar problem on a V3 406 and a V3 412, speech quality was poor generally and abysmal on conferences. Avaya kindly knocked up a couple of patch bin files for me that boosted the sound quality.

 

[spike548]

I have had this problem and still have it - no one is sure what the issue is but check out "Conference Call - white noise" thread I posted a while back.

It has been suggested its a conferencing chip problem.

I am looking to replace our IP office 403 with a warranty replacement but my reseller has ditched Avaya in favour of Alcatel and now I am up a creak with out a paddle.

 

[racom]

3.0 removed the analog trunk restrictions. If you have more than 2 parties in the conference call that are on Analog trunk lines, feedback can happen. In my lab, when I hit the 4th call over Analog trunks, the feedback is so bad that you have to drop the line. If all my parties are on the T1 or PRI, clear as a bell. Supposedly, previous releases prevented more than two analog trunks to be added to a single conference.