Help with RT-ac88u network switch issues - causing reboot

[rkalinka]

I have 3x rt-ac88u's in an AiMesh configuration (hardwired backhaul). Latest Firmware Version: (3.0.0.4.386_48263). The ecosystem had been fairly stable for a number of years - with the occasional hiccups. I usually get between 30-50 days before needing to reboot the main router as it locks for whatever reason.

My current issue is that the AiMesh nodes are randomly rebooting (maybe once every 3-7 days) which are causing momentary internet outages for the rest of the ecosystem. The only thing I can see in the logs is:
...
Nov 1 10:17:19 syslog: wlceventd_proc_event(491): wl1.1: Deauth_ind 00:00:00:00:00:00, status: 0, reason: Deauthenticated because sending station is leaving (or has left) IBSS or ESS (3), rssi:0
Nov 1 10:22:17 BHC: Disconnected from CAP.
Nov 1 10:27:17 BHC: Disconnected from CAP.
Nov 1 10:32:17 BHC: Disconnected from CAP.
Nov 1 10:32:22 ahs: [self_healing]pattern_index-[4].
Nov 1 10:32:22 ahs: [self_healing]re_pattern-[BHC: Disconnected from CAP\.].
Nov 1 10:32:22 ahs: [self_healing]take action-[reboot].
Nov 1 10:32:27 %s: %s: Rebooting...
Nov 1 10:32:27 kernel: Emergency Sync complete
Nov 1 10:32:28 WEBDAV Server: daemon is stoped
Nov 1 10:32:29 iTunes: daemon is stoped
...

There doesn't seem to be any other reason for the restarts. I am aware of the network issues with lan ports 5/6/7/8 - but I don't have anything plugged into those ports either. ON a side note, I do also see:

admin@RT-AC88U-A640:/tmp/home/root# robocfg show
Switch: enabled
Port 0: DOWN enabled stp: none vlan: 1 jumbo: off mac: 00:00:00:00:00:00
Port 1: 100FD enabled stp: none vlan: 1 jumbo: off mac: 78:84:3c:c4:e7:73
Port 2: DOWN enabled stp: none vlan: 1 jumbo: off mac: 00:00:00:00:00:00
Port 3: 100FD enabled stp: none vlan: 1 jumbo: off mac: e4:75:dc:22:54:30
Port 4: 1000FD enabled stp: none vlan: 2 jumbo: off mac: ac:1a:3d:7b:d4:61
Port 5: 1000FD enabled stp: none vlan: 1 jumbo: off mac: 00:00:00:00:00:00
Port 7: 1000FD enabled stp: none vlan: 1 jumbo: off mac: f0:2f:74:d7:a6:40
Port 8: DOWN enabled stp: none vlan: 1 jumbo: off mac: 00:00:00:00:00:00
VLANs: BCM5301x enabled mac_check mac_hash
1: vlan1: 0 1 2 3 5 7t
2: vlan2: 4 7t
admin@RT-AC88U-A640:/tmp/home/root#

Any ideas why ports are showing speeds even if nothing is plugged into them? For example, I only have the WAN port (for uplink), and ports 1 and 2 plugged in - there are no other cables plugged into the node. (and where is port 6?)

Is it worth disabling unused ports or has anyone else run into this problem?