If the Xiaomi Outdoor Camera CW100 Dual has an issue where there is no sound on the phone terminal during a call, please refer to the following suggestions:
Check if the phone's volume is set too low, which can cause the sound to be inaudible;
Ensure that the Xiaomi Home App has permission to access the phone’s microphone. If not, enable the necessary permissions in the phone's settings.
Note:
Ensure that the phone is not connected to a Bluetooth headset or external audio device that can be redirecting the sound;
Make sure both the camera firmware and Xiaomi Home App are updated to the latest version;
Restart the camera or the mobile device to resolve any temporary audio glitches.