Homekit, HUE & KNX: Switch set back to off after one hour, reason unknown


I am using Homeassistant as a bridge between KNX and HomeKit and to control HUE lights. My children each have a HUE night light. It is activated when HA detects a KNX switch changing from off to on. And it is switched off, when the switch turns off.

This is working fine and really stable. But last night my older boy cried, because it was really dark. Nightlight was off.

There was one difference: I turned the switch on using HomeKit and after exactly 1 hour it was turned off. While I can see it was turned on by HomeKit in logs, I cannot see why it was turned off.

Do you have an Idea where this behaviour comes from?


Knx state updater - probably the status is not propagated correctly. When it is read the switch reports OFF and this triggers the automation. But its just a guess as I have no clue how you set up any of that…

That was a good hint!

I think I found the problem: The GA “nightlight” is set correctly to “1”. But when the status is read, the GroupValueResponse changes the status back to 0.

(1) Turn on from HomeKit → turns on GA in ETS (visible in diagnose)
(2) Read Status in ETS → Read GA (GroupValueRead) returns a GroupValueResponse “0” → Switch Turned off in HomeKit.

Misconfiguration within ETS. The GA included the switch (input) and the state (output) element of the corresponding mdt sensor. But the Read-Flag (L-Flag) was set for the switch element, not for status. This is wrong and leads to the described state switch when read.

Thx for your help.