I bought an aml-s905d3-cc, and I have a problem, when the board is energized it keeps turning on and off, only when I press a button on the board, then it works normally, but this is a problem for me because when I put the case on and I can’t keep pressing the button on the board, I wanted to know if anyone knows how to solve it. Detail is not power because my source is cable is of excellent quality, providing 5v and 3A
Can you please rewrite your problem? It’s not clear after reading it repeatedly.
Could you restate the issue?
Perhaps you could post an image/video of your setup that show the issue?
I have a similar problem, my AML-S905D3-CC will not boot after a new firmware update as mentioned in the download section. 
Make sure your firmware variant matches your board. The board is not brickable via software update. You can always reflash the board via MicroSD card by moving the boot jumper to not boot from onboard SPI.