diff -ur sox-14.3.1.orig/src/mp3.c sox-14.3.1/src/mp3.c
--- sox-14.3.1.orig/src/mp3.c	2010-01-02 04:12:05.000000000 +0200
+++ sox-14.3.1/src/mp3.c	2010-04-29 13:33:10.000000000 +0300
@@ -56,8 +56,10 @@
  * Sidestep the issue by defining our own mad_timer_zero. This is needed because
  * mad_timer_zero is used in some of the mad.h macros.
  */
-#define mad_timer_zero mad_timer_zero_stub
-static mad_timer_t const mad_timer_zero_stub = {0, 0};
+#ifdef DL_MAD
+  #define mad_timer_zero mad_timer_zero_stub
+  static mad_timer_t const mad_timer_zero_stub = {0, 0};
+#endif
 
 #define MAXFRAMESIZE 2880
 #define ID3PADDING 128