Echo on called end for about 30 seconds


#1

Hello

On my asterisk system users are reporting echo for up to to 30 seconds which
is heard only by the caller. It doesn’t matter whether the call originates
from the office connected to the Asterisk or caller calling in from outside.
It is the caller who hears the echo.

Setup is Polycom IP300 IP phones connected to asterisk via SIP. Connect to
outside via analog lines - TDM04B module.

Asterisk is running on a fanless CPU running at 600MHz. System has 512MB
memory. Four internal SIP phones and rarley more than two callls at any one
time.

Anyone any ideas what I should be doing to reduce the echo?

Angus


#2

have you looked at the wiki at voip-info.org ?

what does your zapata.conf look like ? have you checked the gains on your zap channels ? the fact it’s training out is good, but it should be quicker than that.


#3

signalling=fxo_ls

echocancel=yes
echocancelwhenbridged=yes

rxgain=0.0
txgain=0.0

echotraining is not set - ie commented out - should we have this?

group=1
callgroup=1
pickupgroup=1
immediate=no

context=frompstnanalog
signalling=fxs_ks
channel=1-4

cidsignalling=v23 ; UK CLI detection
cidstart=polarity ; UK CLI detection
group=1
callgroup=1
pickupgroup=1