For your perusal, the output of dmesg on the EAP670, showing what I think are the failure events (at the bottom). I was going to just include the text here, but your system says " Content or title...

@MR.S OK, I reduced the topology to the following: Internet----pfSense----TrendNet TEG-S380 2.5g non-POE | | | ...

@MR.S I reinstalled the SDN controller (latest version) and adopted the device. Within 6 hours the EAP670 disconnected and crashed, requiring a power-cycle to recover. I think this proves the device...

Hank21 wrote @jhg6308 1 What exactly is the instability issue? 2 Will the EAP670 disconnect from the controller frequently? 3 What is the present status of the change? 4 Will the wireless clients...

When looking at the download page for the Controller software, the latest version is 5.14.26.1. When looking for software for the EAP670, that download page lists 5.13.30.8 as the latest version of...

So far so good, no device instability. I will reinstall the controller and adopt the device on Sunday to see if it starts crashing again.