> Subject: RE: [Asterisk-Users] PRI echo issues: solvable? "Kris Boutilier" <[EMAIL PROTECTED]> wrote:
> > On Tuesday 11 October 2005 11:49, alan wrote: > > > After solving the other "low hanging fruit" audio issues in our Asterisk > > > PBX, we are left with occasional cases of severe echo which we have not > > > found a solution for yet. > > > {clip} > > > > > Most calls have minimal, acceptable echo levels. But occasionally, we > > > get a call where the echo is delayed by a substantial amount (sometimes > > > around 250ms), and sounds as loud as the remote party. > > > > Yup. > > > I finally got time to spend on looking into this again. > If you were to use ztmonitor on the channel to record the transmit and > receive sides to separate wav files, drive an impulse down the channel > (ie. a sharp, loud click) and then load the files into a tool where > they could be viewed side by side you'd see the actual echo endpath > (tail) length. How does one use ztmonitor to record into separate files for transmit and receive? My ztmonitor man page doesn't describe how to do this, it only allows one -f File specification. When I monitored a sample conversation with ztmonitor, it recorded both channels in one file. Then I set up a call from the number which gives us "big echo". Although I heard echo when I was on the call, the recorded version of the call did not record the echo. There are two possibilities here: 1. it wasn't recording the incoming call leg. 2. the echo is entirely internal to our system I couldn't see how #1 could be the case when the immediately previous ztmonitor recorded both call legs. On the other hand, I told the remote party to just put the phone down so I have no evidence that any sound they made was missing. But I can't see how #2 is the case either, since it only affects certain phone numbers, and it affects them consistently whenever it happens. I have a feeling I just did something wrong, so I'll go back and try again. I'll also try a greater echocancel= value and see if it helps. Thanks, Alan Ferrency pair Networks, Inc. [EMAIL PROTECTED] _______________________________________________ --Bandwidth and Colocation sponsored by Easynews.com -- Asterisk-Users mailing list Asterisk-Users@lists.digium.com http://lists.digium.com/mailman/listinfo/asterisk-users To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users