UC520 Volume Issues on Conference Calls

Answered Question
Sep 29th, 2010

I have an issue that is duplicated every time we make conference calls to external numbers.   I generate the conference and the 2 other parties can barely hear each other.   I do not have this issue when generating a conference call among other phones here at the office, so obviously it has something to do with the outside lines.  I have 2 FXO cards for our connection to the PSTN.  This happens every conference call (to external numbers) without exception.  Do you think this has to do with ring voltage and if so, what are the commands to  manipulate this?

I've also attached the voice portion of my config if anyone would like to review and see if there's something I can do differently there as well.

I have this problem too.
0 votes
Correct Answer by Vishal Mohanty about 6 years 3 weeks ago

Hello Steve,

Your configuration has:

max-conferences 8 gain -6

under the "telephony-service", here is the command reference for that:


I would bump that to 3 or 6 and see if it makes any difference or not.



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