diff --git a/libs/ardour/ardour/transport_master.h b/libs/ardour/ardour/transport_master.h
index 5b23d08f1f..5800e4d1c3 100644
--- a/libs/ardour/ardour/transport_master.h
+++ b/libs/ardour/ardour/transport_master.h
@@ -43,9 +43,9 @@
 #include "midi++/parser.h"
 #include "midi++/types.h"
 
-/* used for delta_string(): */
+/* used for delta_string(): (note: \u00B1 is the plus-or-minus sign) */
 #define PLUSMINUS(A) ( ((A)<0) ? "-" : (((A)>0) ? "+" : "\u00B1") )
-#define LEADINGZERO(A) ( (A)<10 ? "   " : (A)<100 ? "  " : (A)<1000 ? " " : "" )
+#define LEADINGZERO(A) ( (A)<10 ? "    " : (A)<100 ? "   " : (A)<1000 ? "  " : (A)<10000 ? " " : "" )
 
 namespace ARDOUR {