We are seeing a very strange issue in our WLAN setup. Our access points hang or reboot randomly. We have WLAN controller 4402 with 25 Cisco 1020 Access points. Our syslog server shows for some access points rebooted. While others just hang and then come back online after 10-15 minutes. We have similar code 220.127.116.11 running at other sites and everything seems to be stable, therefore we do not want to upgrade or install a new code. Any suggestions, or help will be highly appreciated by the experts.