diff --git a/static/js/core/app.js b/static/js/core/app.js
index 7734f5f..ffc3c04 100644
--- a/static/js/core/app.js
+++ b/static/js/core/app.js
@@ -465,7 +465,11 @@ function initApp() {
     // Start clock and init time settings
     initTimeSettings();
     updateHeaderClock();
+    window._navClockStarted = true;  // Prevent nav.html from starting a duplicate interval
     setInterval(updateHeaderClock, 1000);
+    if (typeof InterceptTime !== 'undefined' && InterceptTime.onChange) {
+        InterceptTime.onChange(updateHeaderClock);
+    }
 
     // Load bias-T setting
     loadBiasTSetting();