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New Member

No sound in the middle of a VoIP conversation

I have a remote site wich basically consists of a Cisco 1750 with an FXS where two analog phones are connected and a couple of computers with little traffic to the central site.

The central site also has an Cisco 1750 connected to the PBX through an E&M. The connection between these two routers is through a leased line (64Kbps).

They''ve worked without a problem for about an year but suddenly, the problem is that the remote site stops hearing any sound from the central site, but the call isn''t dropped, with the central site always having sound from the remote! After a while, wich can be a few seconds or a couple of minutes, the remote site starts to have sound again.

I''ve done some testing but I didn''t identify any pattern so i don''t have any clue to what may be causing this problem!

Do you have any suggestions?

Is there some kind of debugging that I might do that can show me some clues?

Thanks is advance!


Re: No sound in the middle of a VoIP conversation

Often times complex troubleshooting issues are best addressed in an interactive session with one of our trained technical assistance engineers. While other forum users may be able to help, it’s often difficult to do so for this type of issue.

To utilize the resources at our Technical Assistance Center, please visit and to open a case with one of our TAC engineers, visit

If anyone else in the forum has some advice, please reply to this thread.

Thank you for posting.

New Member

Re: No sound in the middle of a VoIP conversation

Are you running any kind of QOS? You can also use #debug voice ccapi inout . (Make sure you capture the session before you run this) Make a call then sift through the read out.

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