<div>Hello,</div>
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<div>We have an asterisk setup at our client's site using a TE205P. The line to telco is a 23 channels T1 PRI, however the line has random echo problems (about 5-10% of the calls)!</div>
<div>Can anybody tell me if echo cancellation is really needed even at a T1 PRI to the telco? Because people keep saying when they deploy voip solution in Hong Kong using T1 PRI, there is no need of echo cancellation. (even the local Digium distributor)
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<div>Asterisk is 1.2.13, zaptel is 1.2.10. I choosed the MARK2 canceller in the zaptel.</div>
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<div>The setting in zaptel is default:</div>
<div>echocancel=yes<br>echocancelwhenbridged=yes<br>echotraining=yes<br>rxgain=0<br>txgain=0<br> </div>
<div>When I tried to adjust the echocancel value to a higher taps (e.g. 256) or adjust the rxgain/txgain value, I can even hear echo much easier.</div>
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<div>Anyone can confirm with me we should rather turn echocancelwhenbridged=no, or even echocancel=no when we only use a T1 PRI at the zaptel? Or can have other suggestions to try solving this problem? Because of some people's information that T1 PRI does not need any echo cancellation, add a hardware echo cancellation module is not an option here.
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<div><br>I think I need some sort of information from another 3rd party before my boss will even agree to just try something out.</div>
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<div>Really thank you!!</div>
<div>Vincent</div>
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