diff --git a/tests/duplex.cpp b/tests/duplex.cpp
index 1257eea5..1d680b0b 100644
--- a/tests/duplex.cpp
+++ b/tests/duplex.cpp
@@ -14,18 +14,18 @@
 #include <cstring>
 
 /*
-typedef char MY_TYPE;
+typedef int8_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT8
 */
 
-typedef signed short MY_TYPE;
+typedef int16_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT16
 
 /*
 typedef S24 MY_TYPE;
 #define FORMAT RTAUDIO_SINT24
 
-typedef signed long MY_TYPE;
+typedef int32_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT32
 
 typedef float MY_TYPE;
diff --git a/tests/playraw.cpp b/tests/playraw.cpp
index 8a15a960..7f6ccc9b 100644
--- a/tests/playraw.cpp
+++ b/tests/playraw.cpp
@@ -16,12 +16,12 @@
 #include <stdio.h>
 
 /*
-typedef char  MY_TYPE;
+typedef int8_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT8
 #define SCALE  127.0
 */
 
-typedef signed short  MY_TYPE;
+typedef int16_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT16
 #define SCALE  32767.0
 
@@ -30,7 +30,7 @@ typedef S24 MY_TYPE;
 #define FORMAT RTAUDIO_SINT24
 #define SCALE  8388607.0
 
-typedef signed int  MY_TYPE;
+typedef int32_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT32
 #define SCALE  2147483647.0
 
diff --git a/tests/playsaw.cpp b/tests/playsaw.cpp
index c23163ef..ee61f064 100644
--- a/tests/playsaw.cpp
+++ b/tests/playsaw.cpp
@@ -14,12 +14,12 @@
 #include <signal.h>
 
 /*
-typedef char MY_TYPE;
+typedef int8_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT8
 #define SCALE  127.0
 */
 
-typedef signed short MY_TYPE;
+typedef int16_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT16
 #define SCALE  32767.0
 
@@ -28,7 +28,7 @@ typedef S24 MY_TYPE;
 #define FORMAT RTAUDIO_SINT24
 #define SCALE  8388607.0
 
-typedef signed long MY_TYPE;
+typedef int32_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT32
 #define SCALE  2147483647.0
 
diff --git a/tests/record.cpp b/tests/record.cpp
index c5f9cb51..06d398c9 100644
--- a/tests/record.cpp
+++ b/tests/record.cpp
@@ -16,18 +16,18 @@
 #include <stdio.h>
 
 /*
-typedef char MY_TYPE;
+typedef int8_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT8
 */
 
-typedef signed short MY_TYPE;
+typedef int16_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT16
 
 /*
 typedef S24 MY_TYPE;
 #define FORMAT RTAUDIO_SINT24
 
-typedef signed long MY_TYPE;
+typedef int32_t MY_TYPE;
 #define FORMAT RTAUDIO_SINT32
 
 typedef float MY_TYPE;