diff --git a/src/effect_clock.cpp b/src/effect_clock.cpp
index 84ab5a1..72063a4 100644
--- a/src/effect_clock.cpp
+++ b/src/effect_clock.cpp
@@ -24,7 +24,7 @@ void ClockEffect::loop(boolean invert, CRGB fg_color, CRGB bg_color) {
     }
     fg_color = bg_color;
   }
-  if (ntpClient.getTimeValid()==false && ntpClient.getSeconds() & 1==0) {
+  if (ntpClient.getTimeValid()==false && (ntpClient.getSeconds() & 1)==0) {
 	  clear(window, bg_color);
 	  return;
   }