Due to an issue currently under investigation by Jamie, the Guardian nodes for BS, ITMX, ETMX, and ETMY were restarted at ~10:30am PST. The SPM diff monitor was reporting various SWSTATs were being toggled quickly (a few times per second), but the SUS MEDM screens reported no such behavior.
This seems to just be a problem with the reporting of the status of monitored channels. This shouldn't have any adverse affect on the actual operation of the nodes. And it seems to have been a transient problem, since the issue went away after the nodes were restarted. Still investigating.