I have three identical Hue ceiling lights in this room. They are connected via the Hue Bridge. I have been using CocoHue, but yesterday also installed the inbuilt Hue integration app for comparison.
One of these ceiling lights has been behaving oddly for a few days, but I can't think of any updates I ran around that time (It may have coincided but I didn't note the change at the time). I would have suspected the bulb itself of beginning to fail, but it behaves perfectly when controlled directly from Hue, or even via Hubitat when accessing it via Hue scenes rather than directly addressing the bulb as a device.
With CocoHue, when turning off from any colour or white, it turns blue just before finally going out, and therefore it turns on blue. With the inbuilt integration it turns on many seconds after clicking On from the device page, and takes even longer to turn off (and also turns blue just before going out). All the other bulbs are fine.
I have tried changing the positions of the Hue Bridge and the HE hub, just in case signals were interfering with each other in the direction of that bulb. Oh, and I also turned off power to the bulbs for a few minutes and rebooted the hub.
This is a mystery, can anyone shed any light? (pardon the pun)