7 Replies Latest reply on Aug 2, 2012 11:16 PM by pmwrightjr

    Voice quality issue after replacement of AdTran 924e

    pmwrightjr New Member

      I have a PRI delivered on fiber via an AdTran 924e.  Last Thursday, after having been installed in October of last year or so, the AdTran 924e shut down abruptly.  A new unit was installed by our local carrier and ever since then, we have had intermittent issues with voice quality that sound very much like packet drops.  The architecture is as follows:    <carrier network> single-mode fiber > CPE > AdTran 924e > PRI > Cisco 2811 > Cisco CallManager.

       

      The carrier is insisting that nothing can be done on their end but I have been over and over our CallManager system and we have crystal-clear audio on all calls within our network.  The only problem calls are those that go out to the PSTN over this PRI and the problems started with the failure and subsequent replacement of the AdTran. I have looked in great detail at the 2811 router and PRI card and find nothing to suggest a cause.  The PRI interface is completely clean with no errors of any kind and the CallManager system itself is showing no evidence of any problems.

       

      One of the carrier's technicians suggested that there are some settings in the AdTran that can, if not set correctly, result in this sort of thing but the problem is not getting solved and I'm caught in the middle of a multi-vendor squabble about where the problem is.  So my question is... how can I isolate the cause of these voice quality issues?  Secondarily, are there peculiarities of running an AdTran PRI against a Cisco router in terms of the setup (e.g. should the clock be set in a certain way on the Cisco side)?  Anything I could suggest to our carrier for what to look for (it's a large multinational but I'm underwhelmed at this point with their expertise in the equipment they operate).

       

      Any advice will be helpful!

       

      thanks,

       

      paul