Ive deployed an Omada controller and WAPs to 50+ sites but this is the only time that I am aware of this issue happening.

At this location we have 5x EAP653 v1 and 2x EAP610-Outdoor v1

On at least 5 different android devices we are having the same issue with it saying its connected but the connection drops randomly - pinging the switch that the WAP is plugged into is erratic - its completely random sometimes it will reply for 5 seconds then drop off for 5 and come back or reply for a minute then completely drop off for a minute while standing completely still. On a laptop and ipad this issue does not happen, it pings normally and roams just fine between the WAPs

Latency is also high and random, pinging the switch the lowest latency is 10ms and can randomly jump up to 200-300ms for a few pings then to 60ms etc

Things that we have tried:

Using only 2.4 and only 5 GHZ frequency on the SSID
Using WPA-2 encryption
Adjusting the power level on all the WAPs on low, medium and high
Toggling all the roaming features on / off one at a time including 802.11r
Using only channels 36-45 (This is in a rural area so not much wireless congestion)
Using latest firmware and reverting WAPs to an older firmware
Band steering turned off
Factory reset all WAPs and controller and reconfigured from scratch
Setting static IP on phones
Forgetting network from phone and re-adding
All WAPs are hardwired to a switch and mesh is turned off
Using only default VLAN
Turning off WLAN optimization
Changing DKIM to 3
Airtime fairness is disabled
Creating different SSIDs
PMF is disabled

Some more things have been tried that I cant remember, at this point I am at a loss. TP-Link phone support has been unable to help resolve either - has anyone come across anyting like this before?