Once the video controls disappear user cannot access them. On selecting any video app says double tap to access video controls but on double tapping nothing happens except it says 'video'.
1) Switch ON voiceover.
2) Login to edX app.
3) Tap on any course.
4) Tap on 'Courseware' tab.
5) Tap to access any section which has video.
6) Play any video.
7) Let video controls disappear first.
8) Double tap on the video to access video controls.