Unifi "stuck" APs

Hey,

maybe somebody saw that before. I use unifi alot, in the past so far so good. But Recently I have some wweird issues with some APs in a site.
Controller is a UCK-G2 running about 50 AC-Pro; Router a Netgate 7100 and switches are Aruba PoE 2530.

As said so far so good, network is fine running since >12 month. But recently since some weeks sometimes Access Points get unreachable, “Greyed out in the controller” I can’t restart them by Controller and the controller show them as heartbeat missing or diconected.

When I manually reboot the AP by toggel the switch port PoE it comes up after some minutes again. It’s not a specific AP it seems random. Also the AP is still answering to pings but not letting me connect via ssh.

Thankful for any Idea. May the CKG2 to small for 50AP’s I noticed the memory of the little guy sometimes hit >95% but would that cause this problem? On other sites I have with about the same AP Numbers I use a VM Based controller with more ram.

Thanks!

Controller Version 6.1.71
AP Firmware 4.3.28.11361

They claim a MAX capacity of only 40 access points so I would say it’s overloaded.
https://help.ui.com/hc/en-us/articles/217549368-UniFi-Cloud-Key-s-Device-Management-Limit

Thanks, thats what I thought too. Will move them to a VM and have a look if it gets any better.