Working w/ TAC I had a bug generated (CSCul67156). The short of it is AP's failing to send neighbor messages on 2.4GHz radios. This severely impacts RRM (TPC & DCA). Running Cisco WiSM2 ver: 7.5.102.0 with 3600 AP's.
It's visible through WCS/PI or CLI (show ap auto-rf 802.11b <ap_name>).
Not sure if I can put screens in this listserv, but I wrote it up here: http://www.mikealbano.com/ which has the debugs, screenshots and messages you'll see if you suspect your hitting this issue.
Note, the only current workaround I have is resetting the Access Point. That brings it back to normal operation, though I'm not sure for how long.
