diff --git a/media/libsoundtouch/src/soundtouch_config.h b/media/libsoundtouch/src/soundtouch_config.h
index 6807a1a21dc..9275ba8e6ec 100644
--- a/media/libsoundtouch/src/soundtouch_config.h
+++ b/media/libsoundtouch/src/soundtouch_config.h
@@ -13,7 +13,7 @@
 #endif
 
 #ifndef MOZILLA_PRESUME_MMX
-#ifdef MOZ_SAMPLE_TYPE_S16LE
+#ifdef MOZ_SAMPLE_TYPE_S16
 #define SOUNDTOUCH_DISABLE_X86_OPTIMIZATIONS 1
 #endif
 #endif