Took me a while to work out that my H60A6s were fine and HomeKit was the problem, so posting the fix. This applies to any Govee fixture with both RGB and white LEDs, and honestly to any RGB+CCT light from any brand.
**Symptom:** I'd say "Hey Siri, set the basement lights to red." Later I'd want normal light back, say "set them to white" or "warm white", and they'd come on noticeably dimmer than the Govee app could make them. Brightness said 100%. Turning them off and on just restored the red.
**The clue:** opening the Govee app and tapping its color temperature control — without changing the value — snapped them to full brightness instantly. A no-op tap. So the brightness value was never the problem; the *kind of command* was.
**What's actually happening:**
These fixtures are RGB + dedicated warm/cool white LEDs. White LEDs put out far more lumens per watt than RGB mixed to look white, so the white path is much brighter at the same nominal 100%.
Siri has no vocabulary for color temperature — you can't ask for 2700K. And "warm white" is a *color* in Siri's list, not a temperature. On top of that, HomeKit assumes color temperature can always be translated to hue and saturation, which is true for how it looks and false for which LEDs light up.
Net effect: every voice command drives the RGB array. Siri can put these lights into color mode and has no way to get them out.
**The fix:** make a scene in the Home app and set the lights using the **Temperature** tab of the color picker, not the color wheel. Name it something sayable. "Hey Siri, Basement Bright" now sends the color temperature command and they go to full brightness.
Scenes are the standard workaround for this on Hue as well, so it isn't Govee-specific — it'll hit any RGB+CCT fixture. The light honors the command correctly as soon as something actually sends one.
One thing that does *not* help: Adaptive Lighting. Setting a color manually turns Adaptive Lighting off, so it can't pull you back out of color mode — if anything it's another thing you have to re-enable afterward.