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New Member

VoIP problems

I´m configuring two Cisco 1751V router for data and voice service between two sites. This router has two voice ports in both sites, two FXS in one end and two FXO in the other.

Sometimes, when a customer in site A makes call to site B, or viceversa, the customer in the far end can´t listen to the customer in the near end. I´m using the MLPPP with cRTP.

What can be the problem? Is it a configuration problem? or hardware problem?.

Cisco Employee

Re: VoIP problems

This could be a problem with cRTP. Make sure you are runing the latest verions of IOS, there have been several issues associated with cRTP in older version of IOS.

New Member

Re: VoIP problems

I´m working with c1700-sv3y--mz.122-4.xw

Do you Know what version have I to use?

Cisco Employee

Re: VoIP problems

I would start with looking at the QoS. If the audio is there sometimes the router is set right. The bad QoS will cause the audio to not pass. Yoe are running a current IOS which has many fixes in it. If I were to suggest anything it would be 12.2(6a) or later. This has DSP fixes in it. But you havent mentioned seeing any DSP errors so I would think the code is working.