[cisco-voip] Echo on IP Phones through PRI

[Steve G]

CSCsd54344


On 5/10/07, Matthew Melbourne <matt at melbourne.org.uk> wrote:
>
> Thanks Steve. We have an upgrade planned for our voice gateways in an
> forthcoming maintenance window, where we'll try 12.4(latest) mainline.
> Are you aware of any bugs which document this issue?
>
> Cheers,
>
> Matt
>
> On 09/05/07, Steve G <smgustafson at gmail.com> wrote:
> > 12.3(14) will deffinietly give you echo issues.  it is the DSP firmware.
> > either get new DSP firmware from TAC, or upgrade IOS.  I am using 12.4
> (8)b
> > with no issues.
> >
> > Steve
> >
> >
> > On 4/18/07, Matthew Melbourne <matt at melbourne.org.uk> wrote:
> > >
> > > We are getting sporadic issues from users on IP phones who are hearing
> > > echo on external calls. From this document is would suggest that echo
> > > on IP Phones is caused by hybrid echo and not any local acoustic echo.
> > >
> > >
> > http://www.cisco.com/warp/public/788/voice-qos/echo_ipphone_gateway.html
> > >
> > > The MGCP-controlled voice gateways are all running 12.3(14)T7 with DSP
> > > firmware 4.4.708. In CallManager (4.1(3)SR2), echo cancellation is on
> > > for each port, with a "default" echo cancellation coverage of 64ms.
> > > Input gain and output attenuation are set to 0dB.
> > >
> > > I have seen suggestions to include the "echo-cancel erl worst-case 3"
> > > command on the voice ports. Can this help in situations of occasional
> > > echo?
> > >
> > > Are there any other parameters changes which could help? Could it be a
> > > code/DSP firmware issue? I haven't found a specific echo-related bug
> > > relating to this particular IOS and its embedded DSP firmware.
> > >
> > > On occasions, the start of the call is fine but echo comes and goes
> > > during the call.
> > >
> > > Is there a quick way of finding out which voice gateway a call is
> > > terminated on (we have 8, and all could be used in a round-robin
> > > fashion for outbound calls).
> > >
> > > Cheers,
> > >
> > > Matt
> > >
> > > --
> > > Matthew Melbourne
> > > _______________________________________________
> > > cisco-voip mailing list
> > > cisco-voip at puck.nether.net
> > > https://puck.nether.net/mailman/listinfo/cisco-voip
> > >
> >
> >
>
>
> --
> Matthew Melbourne
>
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