I recently bought a s905x4-bu set-top box, model amino h200, 2G+8G, gigabit network port, no Bluetooth and wifi.
I have to say that it is better made than the unknown brands, with a metal shell and weight. The remote control is also easier to use than most foreign trade boxes, and it also supports poe power supply.
There is an official website where you can download the firmware. It is Android 12, can use adb, and does not support Dolby Vision.
I tried the dtb of s905x4 but it didn’t work. Later, I used the mik tool to extract the dtb in the firmware package boot.img, but it didn’t work.
Later I thought that maybe the machine was not unlocked in the first place. Turn on the machine and press the reset button to enter recovery. It is a very old one, which means that you can double-clear and flash the packages in the sd card or u disk. It is a bit like the interface of flashing Android phones ten years ago.
The firmware package is zip. After decompression, you can directly see boot, bootloader, recovery, etc. I am a novice and don’t know how to unlock bl. I would like to ask for teaching and exchange research.
This is my first communication. I hope you can support me. Thanks！
This is the official firmware download address