Download Android 7.1 firmware for Minix Neo U9-H TV Box from or here, here or here. Download Android 6.0.1 stock firmware for Minix Neo U9-H TV Box from here. Download previous firmware from here. Download Amlogic USB Burning Tool v2.0.8 from here or download Amlogic Burn_Card_Maker v2.0.2 from here.
Model: Minix Neo U9-H TV Box
Image file size: 610 MB
Platform: Amlogic S912
Image name: U9-H-Android7.1-FW001.img
Model / product: NEO-U9-H
Build number: q200-user 7.1.2 NHG47L 20180814 release-keys
OTA update procedure
1. All Apps -> System update (MINIX OTA app) -> Check for updates
2. Download the OTA update package
3. Confirm to update and let the system to reboot and complete the update process
Caution: Please do not update firmware unless you know what you are doing, you really want it or it is absolutely necessary. Firmware updates may occasionally have bad results, like bricking your device, temporarily or permanently. The firmware update process is done entirely at your own risk. Before attempting to update the firmware, back up your data.