diff --git a/radio/src/audio_arm.h b/radio/src/audio_arm.h
index 5e7cbce76..c31fd87ce 100644
--- a/radio/src/audio_arm.h
+++ b/radio/src/audio_arm.h
@@ -40,7 +40,7 @@
 #include <stddef.h>
 #include "FatFs/ff.h"
 
-#define AUDIO_FILENAME_MAXLEN (40)
+#define AUDIO_FILENAME_MAXLEN (42)      //max lenght example: /SOUNDS/fr/123456789012/1234567890-off.wav
 #define AUDIO_QUEUE_LENGTH    (20)
 
 #define AUDIO_SAMPLE_RATE     (32000)