diff --git a/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java b/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java
index e330c52b..5ecf5dae 100644
--- a/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java
+++ b/app/src/main/java/com/xypower/mpapp/MicroPhotoService.java
@@ -429,8 +429,13 @@ public class MicroPhotoService extends Service {
                 Thread th = new Thread(runnable);
                 th.start();
 
-                long expectedHbTime = intent.getLongExtra("HeartbeatTime", 0);
-                long timeout = (expectedHbTime != 0) ? (expectedHbTime + mService.mHeartbeatDuration - System.currentTimeMillis()) : mService.mHeartbeatDuration;
+                long ts = System.currentTimeMillis();
+                long expectedHbTime = intent.getLongExtra("HeartbeatTime", ts);
+                long nextHbTime = expectedHbTime + mService.mHeartbeatDuration;
+                while (nextHbTime <= ts) {
+                    nextHbTime += mService.mHeartbeatDuration;
+                }
+                long timeout = (expectedHbTime != 0) ? (nextHbTime - System.currentTimeMillis()) : mService.mHeartbeatDuration;
                 mService.registerHeartbeatTimer(timeout);
 
                 try {