diff --git a/src/lib/tunes/default_tunes.cpp b/src/lib/tunes/default_tunes.cpp
index 3c44dd5084..fe441676e5 100644
--- a/src/lib/tunes/default_tunes.cpp
+++ b/src/lib/tunes/default_tunes.cpp
@@ -38,7 +38,7 @@
 #include "tunes.h"
 
 // initialise default tunes
-const char *Tunes::_default_tunes[] = {
+const char *const Tunes::_default_tunes[] = {
 	"", // empty to align with the index
 	"MFT240L8 O4aO5dc O4aO5dc O4aO5dc L16dcdcdcdc", // startup tune
 	"MBT200a8a8a8PaaaP", // ERROR tone
diff --git a/src/lib/tunes/tunes.h b/src/lib/tunes/tunes.h
index d50efb21dc..105ee572db 100644
--- a/src/lib/tunes/tunes.h
+++ b/src/lib/tunes/tunes.h
@@ -126,7 +126,7 @@ public:
 	unsigned int get_maximum_update_interval() {return (unsigned int)TUNE_MAX_UPDATE_INTERVAL_US;}
 
 private:
-	static const char *_default_tunes[];
+	static const char *const _default_tunes[];
 	static const uint8_t _note_tab[];
 	static const unsigned int _default_tunes_size;
 	bool _repeat = false;	     ///< if true, tune restarts at end