Works fine then call & voice delays, sync problems

A customer reports occasional strange timing problems. For example, the receptionist dials Pres, he picks up phone, she says hello. (he hears her voice across hallway but not on phone) Then he hears a ring, then her hello through the phone system. Apparently it can also happen to calls transferred from outside though their reporting is fuzzy in this area.

By the time they call me they need it working again urgently, so I remotely restart the system and phones and everything works fine again. Until the problem strikes again a day or two weeks later.

I have not been able to duplicate the problem and I’m not sure where to start looking. The system worked for two years without any reports like this. The problem seems to have begun some weeks after I brought it up to 2.8 in stages from 2.3. Current version is Asterisk is 1.4.22 on CentOS 5. The POTS connection is via a Sangoma card. There are a total of 13 Snom phones. I’ve looked at system load before restarting and found it very low with minimal call traffic.



Any ideas at all on this? I’ve found various problem descriptions that sound somewhat similar but they all seem rtp related, and none seem so hard to reproduce The way this one appears and stays around until the system is restarted is irksome. I’m hoping one of the user reports happens near the end of a business day so I can go on-site and watch it happen before rebooting. Until then it would sure be helpful to get some ideas for what to capture, before blowing away the trail with a restart.