Manta M8P 1.0 3rd USB 2 port not working?

[Shahid-Manzar]

I have been attempting to connect a camera via the 4-pin USB port that is clearly labeled in the manual. I see the pin layout is as shown below (relabelled in green for visibility) but nothing I do seems to work. I tried switching the D+ and D- pins but still no dice. I was wondering if anyone has gotten this to work.

[jonmeredith]

I also failed with an M8P 2.0. I tried wiring D+/D- both ways but no luck.