diff --git a/src/app/datasources/stores/synchronizer.store.ts b/src/app/datasources/stores/synchronizer.store.ts
index 33a0c39..aa25cc0 100644
--- a/src/app/datasources/stores/synchronizer.store.ts
+++ b/src/app/datasources/stores/synchronizer.store.ts
@@ -15,6 +15,9 @@
   ) {
     this.webSocket.list()
       .filter((e: IWSEvent) => {
+        if (!e.msg || !e.msg.changed_fields) {
+          return false;
+        }
         return e.msg.changed_fields.indexOf('backend_status') > -1;
       })
       .subscribe(