@dreischel The only time I saw this issue was on a S905 box when u-boot supplied wrong command line arguments to recovery. Have you tried flashing factory ROM via USB Burning Tool? Also remove aml_autoscript from SD card as it may corrupt the boot process somehow.
The box is not found when I connect it to the pc by otg. I think that the main plate is probably corrupted somehow, because I could connect it a few weeks ago without problems . But when I have the serial debug board I will check what the box is doing (or not) after power on.^^