On Wed, 2010-04-07 at 00:53 +0200, Remco van Vugt (Raffel Internet) wrote: > > I've been testing Sipxecs (4.0.4) running on both Xen (plenty of > resources) and a dual-PIII - 1.4 GHz with 4GB of RAM. Sipxecs turns > out to be a great piece of software, and nearly ready for production > use, except for one annoying problem: a clicking sound is audible on > calls being bridged trough the ACD server. At first, i suspected the > Xen virtualisation because of the well known timing issues with RTP so > I did a fresh install on the P-III box only to find out the problem > still exists! On calls bridged trough the ACD server, a clicking / > chopping / rumbling noise is heard in the background when the other > side is talking (when both ends of the line are silent, no clicking > noise is heard). Voice is sometimes distorted as well. I played around > with codecs, but nothing helps. I tried a downgrade to 4.0.2 but that > didn't help either. > > The setup is as following: > > SipxECS (running in datacenter) <==> INTERNET <==> Phones (connected > trough NAT, tested without NAT). > > Things I have excluded from the equation: > - System load (the ACD calls are the only active calls, being the > caller and the agent. CPU usage is around 3%). > - Software version (problem exists with both 4.0.4 as with 4.0.2). > - Virtualisation (sipxecs is now running on the physical hardware > layer). > - Bandwidth problems (plenty of bandwidth available, sipxecs box > connected by 100mbps to the Internet. Test phone, connected by 100mbps > uplink as well) > > Things I haven't excluded: > - Switch (both test machines are in the same cabinet, therefore using > the same Netgear uplink switch). > - Phones (test phones are Linksys SPA-941 and SPA-942) > > Does anyone have a clue, where to look for the cause of this problem? > I cannot imagine anyone using the ACD in production use with such poor > audio quality. I know the ACD has been subject of discussion for quite > a long time, but for a small setup as I'm proposing right now I hope > it is usable (no more than 5 simultaneous calls, 4 agents).
Are these test calls between those test phones with the ACD, or are the calls coming in from the PSTN? If the latter, what's your connection to the PSTN? I'd try to take a wireshark trace of the RTP at the phone where you're hearing the noise and analyze the RTP stream there. Also...check your switch to make sure that it's running in full duplex mode. _______________________________________________ sipx-users mailing list [email protected] List Archive: http://list.sipfoundry.org/archive/sipx-users Unsubscribe: http://list.sipfoundry.org/mailman/listinfo/sipx-users sipXecs IP PBX -- http://www.sipfoundry.org/
