Cube Orange only works with USB plugged in

The issue I’m having is with the ProfiCNC Cube Orange.

So I’ve tested this Cube on both the ProfiCNC Cube mini carrier board and the Airbot Cube carrier board. In both cases whenever I provide power (plug in LiPo) to my quadrotor the ESCs boot up and the carrier boards receive power, (checked with multimeter) the Cube Orange does not start up.

If I plug the Cube Orange into my computer via the micro USB port or provide 5v power source (portable battery) through the USB, while it is mounted on a carrier board and then plug in a LiPo into my quadrotor the Cube Orange boots up.

If I remove the Cube Orange from the carrier board and plug in a USB 5v power source or my computer, by itself the Cube will not boot.

Thoughts anyone?
Video of error

Setting BRD_BOOT_DELAY=200 fixes this issue.
See this issue thread for an explanation of why.