echo on calls rerouted to pstn only

[prasanthpk]

i have done a voip over a leased line with hdlc eccap

both end i has 1751 router

every thing is fine with in network calls

but when the call is rerouted to pstn i am getting a imensive echo

what is the reason and how can i avoid this

i has applied only ip precedence with a value of 5 only

no other qos used

the same pipe of 64k carries data also

great to hear a equation

[vimoreno]

The QoS settings over your link will not have any effect on the echo you are experiencing.

The two main factors involve in the generation of such echo are: 1. Delay on the PSTN. 2. Not enough Echo Return Loss. In other words, your outbound level into the PSTN is too high and probably your input level into the IP cloud is too high as well. You may want to tune the voice-port that goes into the PSTN by using input-gain and output-attenuation.

[prasanthpk]

thanks sir

i will try

prasanth

[jaiello2000]

Make sure your voice port has output attenuation to 3 or 6, echo cancel coverage is at MAX value (32. You might want to enable Non Linear processing.

Joe