We've received several reports of 2A going to an invalid state, part of the clue is that it may be related to the latest HA2024.08.02, which we are investigating now.
We take the stability of our sensors very seriously, and for this we have done a lot of testing to make sure that the sensors are working in a reliable way, including our own sensors, some of which have been tested for upwards of 3 months, and most of them have been stable and satisfactory.
But still, things can go wrong, 2.4G WIFI environments can be full of noise interference and can be very crowded in a certain band. It is also possible that the complex ap-mesh network becomes a burden for the weak wifi enabled esp32 and it will choose an ap that is further away.
For all these scenarios, we are working on a document as soon as possible, which will point out how to investigate sensor dropouts and how to troubleshoot possible causes in general.
For general cases, we recommend setting a timed reboot for possible routers, e.g. at 3pm, which helps to reduce the burden on the router.
There are a very small number of parts, which may be caused by hardware, which exists, and for such cases it is just a matter of replacing the hardware. Out of the 4500 sensors we make, there may be 5-8 such feedbacks, and they probability will be relatively small.
For general debugging cases, the most useful tool is the online advanced tool https://tool.screek.io/factory_tool/2a/ ,which is suitable for very serious cases (where normal use has been affected), here a basic demonstration of how to connect the 2A to a computer (can be WIndows, Mac, Linux). Then capture the working logs of the device.
Also, a very useful tool is to use the system's ping function to ping a 2a device and see how fast it connects, and if it drops packets:
Also informative are the RSSI's on the 2A properties page, they represent the signal, the larger the number with a negative number, the better the signal. For example -40 is a good signal, -70 is a bit bad.
(the rssi image is from https://eyenetworks.no/en/required-good-wifi-signal-strength/)