diff --git a/source/modules/rtaudio/include/asiosys.h b/source/modules/rtaudio/include/asiosys.h
index 37f7a48a1..c974fc3c0 100644
--- a/source/modules/rtaudio/include/asiosys.h
+++ b/source/modules/rtaudio/include/asiosys.h
@@ -1,7 +1,7 @@
 #ifndef __asiosys__
 	#define __asiosys__
 
-	#ifdef WIN32
+	#if defined(WIN32) || defined(_WIN64)
 		#undef MAC 
 		#define PPC 0
 		#define WINDOWS 1
diff --git a/source/modules/rtaudio/include/ginclude.h b/source/modules/rtaudio/include/ginclude.h
index b627dc2e7..8c609c7ad 100644
--- a/source/modules/rtaudio/include/ginclude.h
+++ b/source/modules/rtaudio/include/ginclude.h
@@ -8,7 +8,7 @@
 	//
 	#define ASIO_BIG_ENDIAN 1
 	#define ASIO_CPU_MIPS 1
-#elif defined WIN32
+#elif defined(WIN32) || defined(_WIN64)
 	#undef BEOS 
 	#undef MAC 
 	#undef SGI