Solutions:
If the other party can not hear voice, pay attention to know whether the delivery hole is blocked or whether there is foreign matter in the delivery hole. If it is confirmed normal, it can be detected from both sides of the call.
1. Due to usage habits, when holding a mobile phone with the right hand, the little finger of the right hand will probably block the microphone input hole at the lower end of the phone (the hole nearest to the left side of the USB charging interface), resulting in no sound in the microphone when sending messages. It is advised to remove the little finger of his right hand and try to see if it returns to normal.
2. Try to make a call with others when the signal of mobile phone is normal. If it is normal, it may be the phone problem that the receiver.
3. If own voice can not be heard when talking with others, and the signal is normal, open the system's own "record" software to record and see if it is normal. If the normal master MIC hardware is ok, and if it is not possible to record, it is suggested to go to the Xiaomi authorized after-sales center for inspection.
4. Whether the third-party calling app or recording software have been installed, and try after uninstalling.
5. Check whether the main mike is clogged with foreign matter. If it is found, it is recommended to go to the after-sales center to clean up, rather than deal with it by one's own.
If none of the above methods solves the problem, it is suggested to restore factory settings; but if it is still invalid, it is advised to take mobile phones to Xiaomi after-sale center for inspection.