Driven slightly demented by Zigbee2Mqtt over past few days

I’d noticed that a keypad I use for controlling Alarmo had been suffering from delayed responses to input or commands from HA so I had a look in Z2M itself for insights.

For some reason NONE of my devices has an LQI at all (all at 0), however if I use the map tool, I can see that the nodes are reporting link quality.

I can also see that the keypad is occasionally linked with two routers (??), mostly just with one, and very occasionally with none at all.

So confused.

and a few seconds letter the keypad is just floating…

So just an update…

I tried to upgrade my version of ‘edge’, which kept failing. The addon installed but wouldn’t load, and I could see in the supervisor log there was a loop where the watchdog kept detecting a problem and reinstalling it. It never managed to sort itself out.
So I uninstalled ‘edge’ and installed the normal zigbee2mqtt addon and restored my configuration file.
Eventually that worked but there was no change in signal strength.
However this morning I’ve checked and there’s been a big improvement, viz:

I still don’t have a clue what the 0x00158d0000408366e device is, or know how to find it, or know how to stop new devices connecting. In theory this is not permitted but they keep joining anyway…