--- a/scripts/netifd-wireless.sh
+++ b/scripts/netifd-wireless.sh
@@ -280,7 +280,7 @@ _wireless_set_brsnoop_isolation() {
 	json_get_var isolate isolate
 
 	[ ${isolate:-0} -gt 0 -o -z "$network_bridge" ] && return
-	[ ${multicast_to_unicast:-1} -gt 0 ] && json_add_boolean isolate 1
+	[ ${multicast_to_unicast:-0} -gt 0 ] && json_add_boolean isolate 1
 }
 
 for_each_interface() {