diff --git a/src/beep.h b/src/beep.h
index 737d3e3..2027655 100644
--- a/src/beep.h
+++ b/src/beep.h
@@ -50,7 +50,7 @@ int beep_test(void);
 #include <alsa/asoundlib.h>
 #include <math.h>
 
-#define FRAMES (SAMPLE_RATE*2) //16384L
+#define FRAMES (SAMPLE_RATE*2L) //16384L
 
 int16_t buffer[FRAMES*2]; /* 16bit stereo sound samples */