In this blog post we’ll list download links for different modem files for Xiaomi Mi5 (gemini) phone. You can try flashing different modems on your phone if you have some issues with network connection and call issues. Always remember to make backups of your current system.
To install different modem on your Xiaomi Mi5 you must have TWRP Custom Recovery installed on your device. Then simply boot into custom recovery mode and install downloaded archive, reboot into system after installation.
Xiaomi Mi5 Firmware and Modems for TWRP installation
This firmware is also suitable for AOSP based Custom ROMs.