If the Xiaomi Smart Camera C100 has an issue that there is no sound on the phone terminal during a call, please refer to the following suggestions:
1. Check if the phone's volume is set too low, which can cause the sound to be inaudible;
2. Ensure that the Mi Home/Xiaomi Home APP has permission to access the phone’s microphone. If not, enable the necessary permissions in the phone's settings.
Note:
1. Ensure that the phone is not connected to a Bluetooth headset or external audio device that can be redirecting the sound;
2. Make sure both the camera firmware and Mi Home/Xiaomi Home APP are updated to the latest version;
3. Restart the camera or the mobile device to resolve any temporary audio glitches.