Download Android Pie 9.0 firmware for X96 Max Plus TV Box from here or here. Download a newer firmware version from here. Download Amlogic USB Burning Tool v2.1.6 from here or download Amlogic Burn_Card_Maker v2.0.2 from here.
Archive name: X96Max_Plus_S905x3_2GB_20191101
Archive file size: 657 MB
Model: X96 Max Plus TV Box / X96 Max+TV Box
Platform: AMLogic S905x3
System: Android version 9.0
Build number: franklin-userdebug 9 PPR1.180610.011 20191101 test-keys (the same like for MAGICSEE N5 Max TV Box)
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.