When shooting aerial video, why is nothing displayed when I select “output AV to image transmission”? (YI 4K Action Camera)

It may be that the cable used for AV output is not compatible with the standard USB cable. We use a 7-pin micro USB cable. For a detailed definition of CVBS output, please refer to http://bbs.xiaoyi.com/forum.php?mod=viewthread&tid=39615&extra=page%3D1