Switch updates on and off several times a second

I’m using a raspberry Pi with the latest version of Openhab and a pair of Wemo switches. I have had it running on an iPhone so that I could switch on and off two Wemo IOT switches. While trying to integrate MQTT to transmit from a remote temperature and humidity sensor, I find that Openhab2 is looping with the switches cycling from on to off several times per second. I reinstalled openhab, updated it, removed the Wemo and MQTT bindings and rebooted. After reinstalling I have the same issue. Here’s what the log shows:
2018-07-22 10:00:16.497 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.503 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.506 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.529 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.533 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.537 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.539 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.756 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.770 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.773 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.777 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.781 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.786 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.796 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.802 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.808 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.812 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.825 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.832 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

2018-07-22 10:00:16.852 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from ON to OFF

2018-07-22 10:00:16.890 [vent.ItemStateChangedEvent] - PoolRoomFan1 changed from OFF to ON

I know it’s probably operator error (as they say). Has anyone run into this? Any suggestions would be appreciated.

Can you post your items and related rules, please?

I am not using rules when I experience the looping (the looping prevents rules from firing correctly so I gave up on trying rules until the looping is solved).

Once I installed the Wemo binding, the two Wemo switches were “discovered” and added from Paper UI.

When I go to the control “tab” in Paper UI and click the switch, it starts cycling.

In my openhabian@opehHABianPi:/etc/openhab2/items/home.items file all references to the switches have been commented out. There is nothing in home.things. All items in the home.sitemap file are commented out. I’m assuming that the files are only the ones created automatically by Paper UI and I haven’t found those files to view.