Hi,

What's the type of the Ethernet cable? I think it's better for you to use cat 5e or above Ethernet cable. And the Ethernet cable should be less than 60 meter.

Wireless connection is susceptible to environment interference, it may cause the unstable connection problem and SSID disappearance problem. You can scan the wireless environment by tools, such as inSSIDer or wifi analyzer, and do the wireless optimization according to the scanning result.

1.  Set the channel width of each EAP to 20MHz to reduce the wireless interference.

2. Set the channel of these EAP to 1/6/11 channel respectively in 2.4G radio and set different channel (36/40/44/48) in 5G radio. It will reduce the wireless interference between each EAP.

3. What’s the distance between each EAP? If the distance is less than 15m, you should lower down the TX power of EAP.

I guess what I'm asking is if there is a way to confirm exaclty what the cause is, like a diagnostic I can do.