First, there is no sound in the 5G call. If the 5G network is unstable, it will affect both 5G and 4G data networks, thus affecting voice calls. It is recommended to turn off the 5G switch before use. When the 5G network is stable, go to Settings-Mobile Network/Dual Card and Mobile Network (select the corresponding SIM card)-Enable 5G, turn off the 5G switch, and then check the call.
2. Use the telecom card, turn on the VOLTE function, and there is no sound during the call. It is suggested to select "Turn off Telecom VOLTE" from the drop-down notification bar, or enter mobile phone settings-mobile network (dual card and mobile network)-enter telecom card-VoLTE HD call, and then check the call after turning off the function. Some models turn on the VoLTE function by default, so you can contact the operator to turn off this service.
Three, the use of mobile, China Unicom, telecommunications (VoLTE is not turned on) can not hear the sound processing method:
1, try to adjust the volume of the mobile phone;
2. Try to dial the replacement number to check the reason of the other party's mobile phone;
3. Check whether the receiver is blocked;
4. Check the cell phone signal and try to switch to a better network environment;
5. System upgrade. The new version of the system improves the compatibility and stability, and optimizes the performance. Please go to Settings-find the system upgrade and check the system version information. If it is not the latest version, it is recommended to upgrade the experience.
6. Restore all settings, and go to Mobile Settings-System Management/More Settings-Backup and Reset/Restore Factory Settings to restore all settings. This operation will cause the logged-in third-party software account to log in again, but it will not clear the photos, videos and other files stored in the mobile phone. Before restoring all settings, please ensure that the use of some third-party software will not be affected. In order to avoid data loss caused by abnormal operation, it is recommended to back up the important data of the mobile phone first.
If the above methods are not improved, you can take your mobile phone and valid purchase voucher to the service center for testing and processing, pay attention to the official WeChat account "vivo" or "vivo customer service" to check the address and telephone number of the service center, and suggest calling before you go to ensure that a staff member receives you before you go to avoid wasting precious time.