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misconfigured or damaged SIP phone
Speaker phone environmental issues
SIP network is causing echo back to SIP phone
Hardware echo cancellor (if Sangoma Hardware equipped with one) not active
Bad PSTN line ( for analog PSTN lines)
Misconfigured or damanged damaged SIP phone
If SIP user(s) hear their own voice when speaking (i.e. echo), verify that the SIP phone is not the culprit. Try making an outbound call with another SIP phone in place of the current one, or make an output call via another SIP phone sitting at another location in the environment/office.
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If your Sangoma card is equipped with a hardware echo canceller, verify that it is active. To find out if your Sangoma card has a hardware echo canceller (and verify if its active) please visit this link:
Echo Canceller Being Used.
Please visit the following link in order to take an audio trace to identify where the echo is being caused:
-> Take an audio trace from Sangoma card or DAHDI signalling layer
The above link will help you identify if echo is being caused by SIP side, Asterisk, the Sangoma card, or the PSTN line
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Sometimes your analog PSTN line (or analog cabling inside your building up to the demark) is causing the echo. This can cause echo that is very severe that the Echo canceller on your Sangoma card (if equipped) cannot remove. In order to identify this, please take an audio trace from your Sangoma card
You will need to send the audio trace to Sangoma support, where they can identify if the echo is created the capabilities of hardware echo to remove.