It's possible that Rydeen changed the design slightly. That happened with one of the TomTop cameras -- see posts starting
here (around Sep 19, 2013), and my reply on Nov 13. TomTop added resistors to their voltage converter, I suspect to counter the 'blazing hot' problem some of their cameras had (when powered from 12V for a long time).
It's also possible that your Rydeen is a counterfeit.
We've seen that happen with a BOYO camera (also see post #99 there). There are other Chinese cameras that look very similar to the Rydeens.