@James-Harding i'd guess the mjpg_streamer is using most of available current, causing dht sensor to error state and would increase available current for dht sensor or pin20 also used by mjpg_streamer.
Sounds interesting, but what makes this platform any better than the major competitors, Brillo/Weave, IOT Eclipse, Apple HomeKit, etc, which have nearly unlimited resources and a reputation. I understand that you have built something for the onion, but it wouldnt be that difficult to duplicate for another platform.