[cisco-voip] multi-site conference call voice quality degrades over time

[Kris Seraphine]

Hi

 

I have a customer with a small two site cluster.  When they hold
conference calls, everything works fine for the first 15 - 20 minutes
but then the participant in the remote site will complain that the audio
becomes choppy or sounds like they're "under water".   These are meet-me
conferences initiated by a user at the central site (where the
callmanagers are) using the callmanager software conference bridge.  The
remote user calls across the WAN (g729) and uses a dsp resources in a
1760 for transcoding. 

 

After 15 minutes or so the call quality will degrade for the remote
participant but other participants are able to hear the remote user and
each other fine.  If the remote user hangs up and calls back into the
conference, it will sound fine but degrade again after 15 + minutes.
During one conference a user called in to the conference 4 times and the
call always degraded after 15 minutes.  

 

I don't think the WAN is an issue.  They have MPLS with guaranteed
realtime bandwidth for 3 concurrent calls.  Callmanager locations
enforce this limit and we've never had any call quality complaints
except for these conferences.  

 

I have a case open with TAC but we're not getting very far with them.
I'm wondering if anyone else has experienced a similar issue.    

 

Kris Seraphine
Senior Technology Specialist

Clifton Gunderson Technology Solutions
1111 Deming Way suite 101
Madison, WI  53717
Phone: 608.833.8638
Fax: 608.833.0194
Direct: 608.662.7640
Web: www.cliftoncpa.com <http://www.cliftoncpa.com/> 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://puck.nether.net/pipermail/cisco-voip/attachments/20050217/cecc30d7/attachment.html