diff --git a/dump1090.h b/dump1090.h
index 15e5b16..a34e569 100644
--- a/dump1090.h
+++ b/dump1090.h
@@ -133,7 +133,7 @@
 
 #define MODES_OUT_BUF_SIZE         (1500)
 #define MODES_OUT_FLUSH_SIZE       (MODES_OUT_BUF_SIZE - 256)
-#define MODES_OUT_FLUSH_INTERVAL   (60)
+#define MODES_OUT_FLUSH_INTERVAL   (60000)
 
 #define MODES_UNIT_FEET 0
 #define MODES_UNIT_METERS 1