The reason for the echo of the mobile phone can be attributed to the problem of the mobile phone itself and the network problem, and the cause of the mobile phone itself may include the reason of your own mobile phone and the reason of the other person's mobile phone.

It is normal for there to be echoes on the network, mainly due to the following reasons:

1. If you make a landline call, it is the echo caused by the conversion of the two or four lines of the landline subscriber line.

2. If you are calling a mobile phone, it is the echo caused by the delay of the wireless encoder.

Therefore, in all networks, there are echo suppressors to prevent echoes. But in some cases, your call path bypasses all the echo suppressors in the network. In this way, there will be an echo on the phone.

3. There is a problem with the design of the phone itself. Normally, most of the echo problems caused by the mobile phone itself are due to the poor isolation of the transceiver loop, which has little to do with the sealing of the fuselage. This is most likely due to the phone's own design, such as the loud sound of the earpiece and the high sensitivity of the microphone, which causes the sound to be transmitted back and cause echo. If your phone has a long-term echo when you are on a call, it's likely that this is the problem. (This is the key in this article)

The most straightforward way to test whether your phone is experiencing echo due to this is to use a headset to make a call, and if there is no echo when using the headset, it means that the echo is due to a defective body design.

4. The network causes echoes. This is mainly due to the fact that the transmission of electromagnetic waves reaches your phone through a variety of routes, including various reflected or relayed signals. Since the signal reached by the first path is the strongest, the phone always processes this signal. For the delayed signal that reaches the mobile phone through other paths, the mobile phone will eliminate it through a certain algorithm.

However, sometimes there are more reflected paths and the signal is stronger, and it is difficult for the mobile phone to eliminate it by a fixed algorithm, so that the echo is formed. If the echo can be successfully eliminated by changing one's position during the call, it means that the original multipath interference route has been changed, which means that the echo is generated from the network and not from the mobile phone.

Therefore, there are many reasons for the call echo and it is complicated,It is not necessarily caused by Xiaomi mobile phones,You can pay attention to whether there is an echo on the phone of a specific user, then it means that it is a problem with the other party's mobile phone,Or whether there is an echo near a certain base station,It means that there may be a network problem,Sometimes an inappropriate mobile phone case will also produce an echo。。。