How to Stop Echoes in Voice Calls

Echo
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Echo is the phenomenon that causes a caller to hear themselves after a brief delay during a phone call or internet voice call. Engineers have been dealing with it since the early days of telephony. While solutions have been found to curb the problem, echo is still an issue with the advent of new technologies like VoIP.

Causes of telephone echo

Sources of echo are numerous. The first source is referred to as sidetone. When you speak, your voice is looped back to you. This is purposefully designed into phone systems to improve the experience of speaking on a phone. As long as the sidetone is heard at the same moment you speak there is no perceived echo. However, hardware issues in phone sets, lines, or software, can cause the sidetone to be delayed, resulting in echo.

Echo can be created when a call is recorded. It is produced when the sound that is emitted by the speakers are recorded by the microphone. It can also be produced when your sound driver is recording all the sounds you hear. In order to determine which one of the two you are producing, do a simple test: Turn your speakers off (set the volume to zero). If the echo stops (your correspondent can tell you whether it does), your issue is the recording process. Otherwise, it's the driver issue.

Echo created by recording a call is difficult to fix without a change in hardware setup. You may reduce it considerably if you take precautions, such as getting your microphone as far away as possible from your phone speaker. Better yet, instead of speakers, use earphones or headsets. Choose headphones that have echo cancellation with good shields. 

For sound driver echo issues, you will need to configure your sound driver so that your microphone is the only recording input device.

VoIP echo

Echo is caused more during voice over internet protocol (VoIP) calls across the internet than over the public switched telephone network (PSTN) and cellular networks. There are simple causes of echo over VoIP calls:

  • A dysfunction in the echo cancellation mechanism of your VoIP phone or device, or in the carriers providing the phone service. There could be defective hardware anywhere on the network, such as in a server along the call's route. VoIP software may also be a cause. 
  • Damaged cables may cause echo, especially those outside of your home or office. Rain and moisture can then cause the echo issue.
  • A smartphone casing may cause echo.

VoIP breaks voice into digital packets and sent over the internet. These packets are delivered to their destinations through a packet switching process and reassembled into the original message at the endpoint. This trip potentially runs into latency or a noticeable lag between when the message is spoken and when it is received. Packets may be lost en route, or arrive in the wrong order.

There are numerous tools VoIP systems use to cancel echo produced this way. Unfortunately, there is little you can do on your side to stop VoIP echo other than ensuring you have a reliable internet connection.

Smartphones and echo

If you're experiencing echo on a smartphone, start by figuring out which end of the line is producing the echo, yours or your correspondent's. If you hear yourself on every call, the echo is your problem. Otherwise, it is either on the other end or in the system beyond your demarcation point, in the phone system, and there is little you alone can do.

If your phone is generating the echo, try the following:

  • If you're using a smartphone, try disabling any noise suppression feature in the call settings. It may produce an echo in some situations.
  • Also, try charging your smartphone. If that doesn't work, try restarting it. This is to give whatever echo cancellation mechanism or app running to reinitialize. The app or service may have been disabled for some reasons, which may also be due to a low battery.
  • Try removing the case of from your phone—these can be sources for echo.