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<DIV><FONT face="Courier New" size=2>Hello Giovanni and everybody,</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Thanks a lot for your
suggestion.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Unfortunately, that does not help. With
READ_SIZE=16, I got vibrating voice on the speaker phone. With READ_SIZE=80, the
voice came back to normal and the echo is more reduced but still noticeable. I
finally changed it back to 160 as it seems to affect a lot of things in
chan_zap.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I am sorry that I didn't properly explain
the setup I have. I think this issue happens because I use wireless handset.
Here is my actual setup:</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New"
size=2>
--------------- out
------------<BR>
| |
<--- | |<BR>Wireless
handset <--> Base phone <--> FXS (TDM400P) <--> | ZAP Channel
| | Asterisk |<BR> (Mic
muted)
| |
---> |
|<BR>
--------------- in
------------<BR>
^<BR>
Monitor()</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>The delay between the original voice going
out from asterisk to the phone, and its echo coming back to asterisk is about
104 ms, assuming that Monitor() application wrote both files at exactly the same
time. How did I find that? I loaded the "in" and "out" files created by
Monitor() application into Audacity (audacity.sourceforge.net). I could not find
any other method to find this delay. Does anyone know a better and more accurate
method?</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>When I did the same thing using X-Lite with
below setup:</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New"
size=2>
--------------- out
------------<BR>
| |
<--- | |<BR>PC (X-Lite)
<--> | SIP Channel | | Asterisk |<BR>(Mic
muted)
| |
---> |
|<BR>
--------------- in
------------<BR>
^<BR>
Monitor()</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>There is no sound at all on the "in" file
created by Monitor() application, indicating that there is no echo at all as the
microphone on X-Lite was muted.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Since the echo on FXS is consistent, there
must be a way to eliminate it. The question is how? I think it can not be done
only by changing the configuration parameters related to echo, especially with
this huge delay.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Do you have any other
suggestions?</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Cheers,</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Anto</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=giomiano@gmail.com href="mailto:giomiano@gmail.com">Giovanni
Miano</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=asterisk-users@lists.digium.com
href="mailto:asterisk-users@lists.digium.com">Asterisk Users Mailing List -
Non-Commercial Discussion</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Sunday, January 15, 2006 2:27
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [Asterisk-Users] Reducing
echo on FXS port</DIV>
<DIV><FONT face="Courier New" size=2></FONT><FONT face="Courier New"
size=2></FONT><FONT face="Courier New" size=2></FONT><FONT face="Courier New"
size=2></FONT><FONT face="Courier New" size=2></FONT><BR></DIV>Try<BR><BR>In
chan_zap.c change the following line:<BR><BR>#define READ_SIZE
160<BR><BR>to<BR><BR>#define READ_SIZE 16<BR><BR>In
zapata.conf<BR><BR>jitterbuffers=40<BR><BR>This will also increase system load
by a factor of 10. <BR></BLOCKQUOTE></BODY></HTML>