Hi,
I got a quite strange issue after creating KNX binary sensors for connected thermostats. As expected and visible in the group monitor thermostats periodically send a status object with constant off value, whereas the value of the corresponding entity changes frequently (randomly ?). Previously imported the KNX project file and created respective entities, while I haven’t seen any issues / challenges there.
To add on, I’m facing similar problems with standard KNX sensor entities to e. g. display current room temperatures. While objects in group monitor show mostly constant or at least steady values, respective entity values are likely mixed-up from different sensors or even completely random.
Well, if that monitor screenshot isn’t filtered (shows all telegrams for that GA), I’d guess that’s a configuration issue.
Of course I did filtering, both for the binary, as well as for the float objects and mapped entities. Somehow it seems periodic updates from different sources overwrite the values of all entities, even though all KNX objects are of type Incoming / GroupValueWrite. Is there some (non obvious) flag to control this behavior?
There’s no disable_randomize_calue flag 
As I said, probably wrong entity configuration.
Hmm, what could / should I do here in a different way? The options / defaults provided all seem to make sense.
Is it probably necessary to provide the respective device (MDT IP Interface) in the lower section, even though not shown to be mandatory?
No, device is optional, and shouldn’t be the interface.
Config looks fine, so have a look at that GA in the monitor again.
Filtering in group monitor for e. g. src=1.1.9 and dst=1/2/1 give this picture
whereas the entity itself provides following details
Why would you filter for source? Just do the group address. Another device may use it too.
All thermostats are sending there binary values to the group 1/2/1, whereas receiving entities are explicitly mapped to specific sending sources. Since group monitor allows for filtering by sources, I expect at least that there is (can be?) a 1:1 mapping between source object and receiving entity or do I miss a point here?
That’s not how Knx is supposed to work - independently of HA. Every function shall use its own GA, source is mostly just for debug purposes.
OK and thanks a lot. Meanwhile I feared this could be the root cause for all the recent hassle, while initially assuming at least in the HA-context KNX GAs would mainly be used to define data types. So, time to get back to ETS …
You could use trigger based template entities for that maybe as a workaround … but I’d recommend to go the standard Knx way - will save you some headaches down the road.
Thanks, but I will stick to the standard KNX way and maybe some day ETS even becomes my friend 
