Random Cisco 3702i Access Points no longer connect to 5520 controller

[DAVID]

I am in the process of replacing Cisco 3702i access points with 9130's but I can't replace all 500+ locations at once.  I am starting to notice in Prime 3.10.4 where there are random 3702i access points showing up as not associated with the controller and I have confirmed that with the 5520 controller running 8.10.190.  

This has not always been the case with this model of AP but I am seeing more 3702's just quit associating with the controller while they are still accessible on the network via SSH.

Is this a bug within the AP or something else? 

[marce1000]

  - Start with configuring global AP syslogging on the wireless controller to a  syslog server , then scrutinize logs from APs arriving  and look for hints ,

 M.

[marce1000]

- Start with configuring global AP syslogging on the controller to a
syslog server. Look at the logging from the APs send and look for insights,

M.

[Leo Laohoo]

Depends on the age of the AP. 

The 2700/3700 have several design defects baked in.  

1. The Ethernet port would degrade to 10- or 100 Mbps. 
2. The WiFi radios, most commonly the 5.0 Ghz, would fail.  During OS would "try" to get the radio to wake up and every time this happens the AP would disjoin the controller and come back in (if the AP does not crash).

[Rich R]

And update to 8.10.196.0 as per TAC recommended link below to make sure you have all available fixes.