The POCO X7 Pro supports VoLTE HD voice calls.
For your reference, here is more information about VoLTE HD voice calls:
1. VoLTE HD (Voice over LTE HD Voice Calls) is a voice call technology based on the LTE network, providing a higher quality voice call experience. VoLTE HD calls use high-definition voice coding technology to make calls clearer and more natural, and reduce background noise and call delays;
2. When using the LTE network, VoLTE can continue to transmit data, such as surfing the Internet, downloading, video streaming, etc., while making voice calls without switching networks;
3. VoLTE can reduce dial-up connection time and connect almost instantly after making a call, avoiding the long waiting time in traditional networks.
To enable this feature, please refer to the following steps:
1. You can go to [Settings];
2. Tap [Mobile networks];
3. Select the SIM card that you want to use for the VoLTE HD calls;
4. Tap [Preferred network type];
5. Select [Prefer 5G] or [Prefer LTE]. You can see a VoLTE icon on the upper right corner when you slide down from the upper right to open the control center, which indicates that your device has enabled the VoLTE feature.