Matter lights and change of brightness (bug?)

Hello everyone,
I have lights from WiZ via Matter (WiFi) in use. The lights are connected to Home Assistant and Apple Home via Matter. The control via Home Assistant and Apple Home works very well so far.
However, if I change the brightness of a light in Apple Home and then execute a scene in Home Assistant with a different brightness, nothing happens. However, if I now manually adjust the brightness of the lamp in Home Assistant and then execute the scene, the brightness changes correctly again.

It looks to me as if Apple Home is taking full control of the light and Home Assistant only regains it if I manually adjust the brightness there once.

Is this a Home Assistant, Matter or Apple Home bug?

WiZ has some bugs with Matter that I reported and they’re aware. One of them is precisely ignoring the brightness level in certain situations, especially if the new brightness level is lower than the last one, although I could only replicate if the light was off and you didn’t explicitly send an “on” command before changing the brightness.

I would recommend you to use WiZ with the Home Assistant integration which uses the MQTT protocol of the lights instead of Matter, at least until they fix this and the transitions. That way you can also use the WiZ scenes and dynamic modes that you can set in the app that are not exposed in Matter.

However, if it only happens with that scene and for every brightness and not depending if it’s on or off… maybe it’s a problem with the scene.

I had already tried to contact WiZ. However, the support was useless. In the end, they referred me directly to Matter.

I actually think the lamps are great. There are even situations where they are superior to Philips Hue lights. But the problem with the brightness is very annoying.
I’ve also tried not using a scene, but running it via a script and explicitly setting the lamps to brightness, colour tone etc. But that didn’t change anything.

I use reddit, there’s an account by the name wiz-dude which is from WiZ, that’s why I know they’re looking into it.

Anyway, I also use WiZ lights with Matter, with SmartThings mostly, but also have it added to Home Assistant via Matter so I tried to replicate your issue. It works for me, I can change the brightness from SmartThings perfectly and then activate the scene in HA. Works with more or less brightness and with on or off, so…

Do you use rhythms in the WiZ app? Maybe try to disable them and just use the last state. Rhythms get in the way many times with Matter.

Do you mean deactivate the WIZClick function?

No, I mean disable the Rhythm of the room in the automations section of WiZ app, like the circadian rhythm feature. Maybe you didn’t enable it so then there’s nothing to do there.

I tried a couple more times to replicate your issue with no luck and I don’t think it’s any of the issues I faced before.