I had the same situation and I had to replace my T1 card with the one with hardware echo canceller. All other solutions were failed. May be you need to do the same if you're on a PRI or using PSTN lines. If you're on a pure VoIP network, then its the phones.
<br><br><div><span class="gmail_quote">On 6/30/07, <b class="gmail_sendername">Jordan Novak</b> <<a href="mailto:jnovak@logisticshealth.com">jnovak@logisticshealth.com</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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<p><font size="2">I have three polycom 501 that are all hearing echo. The other party sounds fine but you can hear yourself rather well. The volume does help if lowered but that also makes the other party extremely quiet. Is there any way to control the gain of the mic or stop the microphone from picking up so much from the handset. It only happens while you are on the handset.
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