Yeelight color bulb heating up when OFF (consumption 2W)

Hi all, I’m having an issue. Just got Yeelight bulb 1S (color). All works OK, except when it is off, it still heats up. None of my other brand wifi/led lamps does that. I have the latest firmware updated. Is it a hardware / firmware issue or that is expected? Power is 2W when light is off and 9W when light is on maximum brightness.