I’ve been having the solid white LED problem. It worked when I first got it, but stopped after a while after trying to flash a sketch. I reflashed the firmware 0.4.7 via dfu-util, but no dice. particle setup fails after being unable to get the mac address of the device (throws a js error about not being able to get an attribute of undefined). The LED stays solid white.
If I plug the photon into the computer I can get it into Listening Mode and particle setup detects the device, but still fails after trying to access ap.mac.toLowerCase(). The Tinker app does not detect the photon.
I used the dfu-util commands found on the GitHub Latest Releases page (https://github.com/spark/firmware/releases/). The output was along the lines of “Flashed successfully”. I had a few servos attached, but I took them out when I tried flashing.