Resolving Audio Echoes - AT&T Syn248 SB35010 Installation And Configuration Manual

Syn248 Installation and Configuration Guide

Resolving Audio Echoes

If excessive echo occurs on outside calls consistently, there are two approaches you can
take to troubleshoot the condition:
1. Check line calibration and parallel devices. The SB35010 Gateway uses automatic
telephone line calibration to ensure optimal audio performance on outside calls. You
can observe the Gateway line calibration data to understand any telephone line
issues and recalibrate the lines, if necessary. Echoes may sometimes be caused by
other devices using your PSTN lines, or by an outside caller's phone.
2. Adjust Echo Suppression and Line Loop Length settings.
To check line calibration and parallel devices:
1. Log on to the WebUI as administrator. In the navigation menu at left, click Device
Management, then click Advanced PSTN Settings.
2. Select the PSTN Gateway from the Select Gateway list. Line Calibration Data
appears.
3. Check the loss numbers within the Line Calibration Data table for each telephone
line connected to the Gateway. A loss number above 10 indicates good audio
performance.
4. If the loss number is below 10, the system will most often function normally, but
there is an increased likelihood of audio performance issues like echo. If the loss
number is below 10 the following procedures can be used to increase the loss value:
Click the Calibrate button for the affected line.
a.
b. Wait one minute, then click Refresh Line Calibration Data.
5. If the recalibration has no effect, a parallel device such as a fax adapter, alarm
system, DSL modem, or DSL splitter/filter may be connected to the system. Parallel
external devices may affect line calibration. Disconnect these devices from the
telephone wall jacks that are connected to the same telephone lines, as follows:
a. Unplug these non-system external devices from their telephone wall jacks.
b. Recalibrate the affected line.
c. If there is a significant increase in the loss number and improved audio
performance on those lines after disconnecting a parallel device, you may want
to install separate lines for those parallel devices.
Troubleshooting 99
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