I'm hitting a device number limit?

I’ve been steadily increasing my Z2M network and I now have around 48 devices; Aqara wireless sensors, a couple of Hue light bulbs and some Ikea bulbs - so a good mix of battery and powered devices.

I have recently changed the firmware of my CC2531 USB stick to the source_routing firmware as that is supposed to support more devices.

My USB stick is connected to an extension cable and put away from the server.

I have paired a couple devices directly with the USB stick (mostly powered ones), other devices I have paired to the light bulbs.

In other words, I think I have done all the recommended steps to have good throughput, but still I find that I’m losing devices every day. I don’t have concrete evidence, but it feels like every time I fix a device by re-pairing it, another device randomly drops off - in other words, it seems like there is an upper limit of around 45 devices.

Is there anything else I can do to make this more stable? I didn’t start over after updating the firmware; should I delete the whole database and start over to make sure the linkages are correct?
I have attached a screen shot of my Device Map. It seems a bunch of devices are not connected, but they typically work fine.

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Add one or two CC2531 routers. Light bulbs are routers, but the number of devices that can connect through it is limited.

I wanted to give a follow up on this question, in case someone finds this in the future and is having similar issues.
I posted the same question on Reddit and got a lot of suggestions there, which I implemented - with great results so far.

  • I bought a new CC26X2R1 to run as the controller
  • I added three Ikea repeaters spread out strategically through the house
  • I moved the Hue and Ikea bulbs off Z2M and moved them to my Hue system
  • I removed the Xiaomi gateway and moved the sensors from that to z2m - to reduce conflicting channels
  • I moved my wifi APs to channels 1 and 6
  • I kept Hue on zigbee channel 20, moved z2m to channel 25

results after testing for 2 days:

  • wifi is much better, unifi is reporting 99% happiness for all devices, while before I had many devices running around 60%
  • all zigbee devices are working well, no more floating devices on the network map, all respond quickly, no devices falling off the network
  • the ikea bulbs work a lot better on the Hue network; before they were a bit flaky and didn’t always respond, or were slow - no such problems at all anymore.

one quirk: z2m became unresponsive at one point, this was after I had put the CC26X2R1 in a case I 3d-printed. Removing it from the case and restarting it fixed that. Not sure if it was caused by the case, or just a timing coincidence, but I didn’t have the same issue again after removing the case, and I did read about others having similar issue after putting it in a case. So for now I’m leaving it out of the case…

So overall it looks like things are a lot more stable, and I now have a foundation to add more sensors! ( I had 10 additional in a box that I wasn’t adding given the original issues and I didn’t want to make it worse).

edit: the thread on reddit: https://www.reddit.com/r/homeassistant/comments/er3kiv/max_number_of_devices_on_zigbee2mqtt/

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