Hi @allywenzel , I do see this type of situation often. Usally something changes to cause this.  That log "stp_tcn_error" 'Topology Change Notification". Meaning the Layer 2 path or Spanning Tree is changing where all traffic should go. Most of the time, someone plugged in something. Or in your case, most likley a cable or device is misbehaving. As @RaphaelL reccomended, check you RSTP Root and make sure it is it is in fact the Root. Use the following guides to assist in the investigating and mitigation.    https://documentation.meraki.com/MS/Monitoring_and_Reporting/Loop_and_MAC_Flap_Detection_on_MS   https://documentation.meraki.com/Architectures_and_Best_Practices/Cisco_Meraki_Best_Practice_Design/Best_Practice_Design_-_MS_Switching/General_MS_Best_Practices       ... View more