The following information will help you solve issues with Echo when SIP users hear echo.
For the purpose of this discussion, we will be referencing the below diagram:
Call where SIP side is talking and hears echo
There are 4 reasons why you are hearing echo:
- 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 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.
If the echo is removed once replacing the SIP phone, please investigate the issue with SIP phone vendor or IT department to resolve your issue, as this is not related to any effect by the Sangoma card/Software/PBX.
If echo is still present after performing above step, please proceed to next step
Speaker phone environmental issues
Sometimes the room with which you are using your speakerphone in can be the source of the echo. This happens when the echo is actually generated by your voice bouncing off the walls of the room at a delayed rate. To rule out your speakerphone/environment causing the issue, simply try speaking on a regular handset. If the echo issue goes away when speaking on the handset in the same room, you know the issue was due to speakerphone. Try adjusting speakerphone settings to resolve the issue.
SIP network is causing echo back to SIP phone
Quite frequently the issue with echo on the SIP side is actually due to SIP network. A delay in the network can cause the echo.
Try isolating the SIP network from the PBX that is hosting the Sangoma card and attempt to make a call to reproduce the issue. If the issue is resolved with this procedure this means you will require your IT administrator to investigate to resolve the issue
Hardware echo cancellor (if Sangoma Hardware equipped with one) not active
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
Bad PSTN line
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.