diff --git a/CommandDistributor.cpp b/CommandDistributor.cpp
index ad11b22..1714b73 100644
--- a/CommandDistributor.cpp
+++ b/CommandDistributor.cpp
@@ -234,6 +234,6 @@ void CommandDistributor::broadcastText(const FSH * msg) {
 #endif
 }
 
-void CommandDistributor::broadcastTrackState(FSH* format,byte trackLetter,int16_t dcAddr) {
+void CommandDistributor::broadcastTrackState(const FSH* format,byte trackLetter,int16_t dcAddr) {
   broadcastReply(COMMAND_TYPE, format,trackLetter,dcAddr);
 }
diff --git a/CommandDistributor.h b/CommandDistributor.h
index a5751e9..e1dbfec 100644
--- a/CommandDistributor.h
+++ b/CommandDistributor.h
@@ -51,7 +51,7 @@ public :
   static int16_t retClockTime();
   static void broadcastPower();
   static void broadcastText(const FSH * msg);
-  static void broadcastTrackState(FSH* format,byte trackLetter,int16_t dcAddr);
+  static void broadcastTrackState(const FSH* format,byte trackLetter,int16_t dcAddr);
   template<typename... Targs> static void broadcastReply(clientType type, Targs... msg);
   static void forget(byte clientId);