Need Help! Switches actions are coupled with each other and I don't know why!

Hello,

I installed four switches Sonoff S20 which prior were flashed with the Tasmota firmware.
To integrate them I first followed the instructions in the article: https://siytek.com/how-to-set-up-tasmota-mqtt-auto-discovery-for-home-assistant/.
Later on, I discovered that instead of using the integration via the Mosquito Broker it can be done via the Tasmota integration (Ref: https://tasmota.github.io/docs/Home-Assistant/). I did exactly what is described here:
If you have been using SetOption19 1 for device discovery, setting it to SetOption19 0 will remove your Tasmota device from the MQTT device list and add it to the Tasmota integrations in HA.

The switches now appear under the Integration Tasmota.

My problem: Three of them are coupled in their actions: when one is activated (ON or OFF) all three react. The fourth one reacts only when it is activated, i.e. "correctly".
I setup all four switches following exactly the same instructions, so I can not figure out where this coupling is performed.
This unintended effect makes the switches useless, because I have use cases for them where they shall act individually.

Can somebody explain where/how the coupling occurs?
Thanks in advance for advices, hints, explanations!

Tasmota version used in the Sonoff S20: 9.3.1
Home Assistant version: 2021.3.4

Are all of the devices configured with a unique device name?

Hi,

I used different Device Name in the Tasmota dialog “Other Configurations” (this is outside Home Assistant). In this dialog, also a Name [friendly name] 1 can be set, I also used different friendly names for the devices.
These friendly names are showed in HA in the overwiew, section Switches.
In HA I didn’t find any place yet, where I can put a device name.

Do they have unique IP addresses?

Yes, they all have different unique IP addresses.

Hello,

I think, I have found the reason for my problem: in the Tasmota configuration dialog (i.e. outside HA!) MQTT configuration, field topic I had writen the value “tasmota” für all switches, the single switch had a typo, probably produced by me and behaved therefore different.
I deleted the values of this field topic, now the switches behave normal, as they should.

Btw: what is the meaning (and purpose) of this field “topic”. In other words: what is it good for?
According to my experience, the field could be used to couple behavior of several devices, but I do not think, this was the reason at Tasmota to introduce this field.
I know, these are aspects outside of HA, however I would be very glad if I get some answers. Thanks!

… and thank you all for your kindly attention! :+1:

Hi @Troon,

herzlichen Dank für die Zusendung dieses Textes.

Gruß