I have a strange scenario I have been brought into at work. A loading dock that has 3 Cisco 1242ag units started filling the spectrum with noise keeping their set channel at 100% duty cycle. I'm using Cisco Spectrum Expert to locate the devices. When we unplug the AP the duty cycle on that channel drops to almost nothing. When plugged back in it may start again or not. Its hit or miss. We replaced 2 of the APs with other Cisco 1242ag units and had the same trouble. We do not use a controller with these units. Is there a setting on these units that would cause them to broadcast like this?
There is only one SSID in the warehouse. The problems started about the same time the local IT guys replaced the PoE hubs with D-Link PoE switches. What I'm trying today is putting one of my Cisco PoE switches in their IDF and plugging three APs into it to see if the problem recurs with those APs. Its the only common link to all APs in the warehouse. I don't like this line of troubleshooting, but its the only thing they have in common and it started about the time they moved to this hardware.