I think I've found an issue with the RGBGenie Zigbee Micro Dimmer driver. If you start with the dimmer at 100% and issue a setLevel(0,1) to turn the light off with a transition of 1 second, the light does in fact turn off correctly and at the rate specified. However, if you then issue just an "on" command, the light turns on and the switch attribute reports correctly but the level attribute remains at zero when in fact the light turns on to the level you started with. It does not update the level until you hit refresh.
I don't know whether you want to fix the behavior after a setLevel of 0 or just remove the ability to use setLevel of 0. I was never a fan of using it before. I always just turned the switch off instead. But I realized, with setLevel 0 you can get a transition time that is different than the setting in the driver. It's not a huge issue for me since I use setLevel almost exclusively (this only occurs with "on" commands) but I noticed it so I thought I should point it out.
BTW...I love what you did for the dimming/brightening rate qualifier in the driver! Wish every dimmer driver had this!! Very nice.
The micro dimmers are designed to go real low for when you use incandescent bulbs. LED's will ultimately turn off on such a low power setting. The minimum dimming threshold can be set on the module so you can squeeze the most out of dimming when using LED's. All LED bulbs get to a point where they flicker when too low and this level is completely dependant on the manufacturer of the bulb. Some are better than others.
I'm already using a 24v strip connected to a triac cc led driver.
The rgbgenie dimmer doesn't work well with 100% -1% on my 24v srtip.
(changed from 100% to 1% after off)
(From 99% to 1% it works smoothly)
(Normal operation at start level change)
In the same light the Hlc-821 dimmer works fine at 100% -1% but unfortunately I can't connect it to an external switch.
rgbgenie dimmer from the same triac cc led driver
For led lights using 36v, 100% -1% works fine.
I realized it was not an issue with hubitat's built-in driver.