index increment bugfix

monitorReceiver.lua

@@ -140,7 +140,7 @@ function get_messages(buffer)
             system.timeout = true
             return
         elseif event == 'monitor_touch' then
-            system.index = (system.index + 1) % #system.components + 1
+            system.index = system.index % #system.components + 1
             break
         end
     end