I recently purchased a 3 Deco M5 kit and I'm quite happy with it in terms of range and speed. However, it is VERY common that it will not pick up an IP address when a device (new or existing) tries to connect to it.
This issue happened with one kit I purchased and upgraded immediately upon installation to firmware version 1.4.4. Because it was happening so much, I exchanged it for another of the same kit. Now, I did not upgrade the firmware, as I thought that could be the issue. Evidently, it wasn't. I keep getting devices (iMac, MacBook, Windows laptop, iPad, Apple Watch, iPhone, smart tv, etc...) to get 169.254.x.x self assigned ips for a while (sometimes seconds, sometimes many minutes or until I give up) instead of an assigned 192.168.68.x IP address.
Looking at the logs, there are several entries of this kind:
"Mon Jul 20 23:20:53 2020 daemon.err udhcpd: no free IP addresses. OFFER abandoned"
Which is very odd, as I have about 25 connected devices, and the DHCP pool is set at 192.168.68.100-192.168.68.250 (in the device that I returned I had changed it to .2-.250, but to no avail).
I thought it could be some issue with the DHCP server, either in the firmware or hardware. But the problem persists with a new device (kit) and older FW.
If I set the IP address as manual, rather than automatic, the device connects with no problem, but really it's a pain to do that, and DHCP should work.
I have not seen this issue in other posts, so I hope someone can shed some light. Otherwise, I will return and look for an alternative whole home system.