The analog phones are a common cause of echo.  Look for settings on the device to use an echo canceler.<div><br><br><div class="gmail_quote">On Tue, Dec 6, 2011 at 8:58 PM, Boris Kovalenko <span dir="ltr">&lt;<a href="mailto:boris@tagnet.ru">boris@tagnet.ru</a>&gt;</span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
  
    
  
  <div bgcolor="#FFFFFF" text="#000000">
    Hello!<br>
    <br>
        We are not using headsets and speaker phones. Only standard
    analog phones connected via Linksys or Audiocodes devices. I have
    tested LG, Nortel, Samsung, Panasonic phones with same result. The
    problem exists only _inside_ my network. So, for example:<br>
    <br>
    Audiocodes -- FreeSwitch -- Linksys  ... echo present (often)<br>
    Linksys -- FreeSwitch -- Linksys echo present (rarely)<br>
    Audiocodes / Linksys -- Freeswitch -- Cisco 5350 -- PSTN (echo never
    present)<br>
    Audiocodes / Linksys -- FreeSwitch -- remote calling party over
    internet (echo never present)<div><div></div><div class="h5"><br>
    <br>
    <br>
    <br>
    <blockquote type="cite">Headsets, speaker phones, calling a remote party over
      high latency.<br>
      <br>
      <div class="gmail_quote">On Tue, Dec 6, 2011 at 8:49 PM, Boris
        Kovalenko <span dir="ltr">&lt;<a href="mailto:boris@tagnet.ru" target="_blank">boris@tagnet.ru</a>&gt;</span>
        wrote:<br>
        <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Hello!<br>
          <br>
              I have tested many phone models with same result. So my
          VOIP isn&#39;t<br>
          properly functioning? Jeff, may You tell me what should I
          double check<br>
          to eliminate echo?<br>
          <div>
            <div><br>
              &gt; Its not possible to have echo in a pure VOIP
              (properly functioning)<br>
              &gt; implementation. The only source of echo would be from
              acoustic echo on your<br>
              &gt; phones which is most likely what you are
              experiencing. A Jitter buffer wont<br>
              &gt; help this problem.<br>
              &gt;<br>
              &gt; --<br>
              &gt; View this message in context: <a href="http://freeswitch-users.2379917.n2.nabble.com/Does-I-need-jitter-buffer-tp7065665p7067246.html" target="_blank">http://freeswitch-users.2379917.n2.nabble.com/Does-I-need-jitter-buffer-tp7065665p7067246.html</a><br>

              &gt; Sent from the freeswitch-users mailing list archive
              at Nabble.com.<br>
              &gt;<br>
              &gt;
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          <font color="#888888">--<br>
            Regards,<br>
            Boris<br>
          </font>
          <div>
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              <br>
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      <br>
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      -- <br>
      Anthony Minessale II<br>
      <br>
      FreeSWITCH <a href="http://www.freeswitch.org/" target="_blank">http://www.freeswitch.org/</a><br>
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      <br>
      <pre>_________________________________________________________________________
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</pre>
    </blockquote>
    <br>
    <br>
    <pre cols="72">-- 
Regards,
Boris
 
</pre>
  </div></div></div>

<br>_________________________________________________________________________<br>
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<br></blockquote></div><br><br clear="all"><div><br></div>-- <br>Anthony Minessale II<br><br>FreeSWITCH <a href="http://www.freeswitch.org/">http://www.freeswitch.org/</a><br>ClueCon <a href="http://www.cluecon.com/">http://www.cluecon.com/</a><br>
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