Wow, that definitely is weird. 😕
There's an article on another forum out there that claimed that the problem was with the WPA implementation on the network. The reason being is because of these strings in the file "Localizable.strings" in the
"ClientController.bundle/Contents/Resources/English.lproj" folder under the
"/System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources" folder:
"wpaIsFailureMIC" = "The wireless network appears to have been compromised and will be disabled for about a minute.";
"wpaIsReplayAttack" = "The wireless network appears to have been compromised and will be disabled for about a minute."
If you don't use WPA though, I am out of ideas.