On 6 February was the same problem with the dark camera. I wrote an email to rlc and got as answer a "The issue has been fixed.". Strong words, nothing happens. And not one "sorry"!
2:22:22 Nicole's room, Cam 8: She has lowered the blinds (see mirror). That is why we did not see anything after the blowing out of the candles. (In the other nights the blinds were open, and that was enough light for the cams.)
I think she knew perfectly well that we could not see anything with lowered blinds and without candles!
That is not correct. Night Vision works with Infrared lights. Cam-Build-in LED or extern.
When you turn off the (normal) light in the room, cam switch to infrared-mode.
If the infrared LED then not work, you can see nothing. Except, there is somewhere a little light from the adjoining room, or from outside. Or a candle.
Randomly four cameras simultaneously without her build-in infrared? This is impossible.
Unless, in the two rooms is a separate (not cam build in) infrared lamp installed, which was switched off.