diff --git a/dlls/dmsynth/tests/dmsynth.c b/dlls/dmsynth/tests/dmsynth.c
index 83a0bcacaa0..ba094a10441 100644
--- a/dlls/dmsynth/tests/dmsynth.c
+++ b/dlls/dmsynth/tests/dmsynth.c
@@ -56,30 +56,30 @@ static void test_dmsynth(void)
     hr = IDirectMusicSynth_QueryInterface(dmsynth, &IID_IKsControl, (LPVOID*)&control_synth);
     ok(hr == S_OK, "IDirectMusicSynth_QueryInterface returned: %x\n", hr);
 
-    property.Id = 0;
-    property.Flags = KSPROPERTY_TYPE_GET;
+    S(U(property)).Id = 0;
+    S(U(property)).Flags = KSPROPERTY_TYPE_GET;
 
-    property.Set = GUID_DMUS_PROP_INSTRUMENT2;
+    S(U(property)).Set = GUID_DMUS_PROP_INSTRUMENT2;
     hr = IKsControl_KsProperty(control_synth, &property, sizeof(property), &value, sizeof(value), &bytes);
     ok(hr == S_OK, "IKsControl_KsProperty returned: %x\n", hr);
     ok(bytes == sizeof(DWORD), "Returned bytes: %u, should be 4\n", bytes);
     ok(value == TRUE, "Return value: %u, should be 1\n", value);
-    property.Set = GUID_DMUS_PROP_DLS2;
+    S(U(property)).Set = GUID_DMUS_PROP_DLS2;
     hr = IKsControl_KsProperty(control_synth, &property, sizeof(property), &value, sizeof(value), &bytes);
     ok(hr == S_OK, "IKsControl_KsProperty returned: %x\n", hr);
     ok(bytes == sizeof(DWORD), "Returned bytes: %u, should be 4\n", bytes);
     ok(value == TRUE, "Return value: %u, should be 1\n", value);
-    property.Set = GUID_DMUS_PROP_GM_Hardware;
+    S(U(property)).Set = GUID_DMUS_PROP_GM_Hardware;
     hr = IKsControl_KsProperty(control_synth, &property, sizeof(property), &value, sizeof(value), &bytes);
     ok(hr == S_OK, "IKsControl_KsProperty returned: %x\n", hr);
     ok(bytes == sizeof(DWORD), "Returned bytes: %u, should be 4\n", bytes);
     ok(value == FALSE, "Return value: %u, should be 0\n", value);
-    property.Set = GUID_DMUS_PROP_GS_Hardware;
+    S(U(property)).Set = GUID_DMUS_PROP_GS_Hardware;
     hr = IKsControl_KsProperty(control_synth, &property, sizeof(property), &value, sizeof(value), &bytes);
     ok(hr == S_OK, "IKsControl_KsProperty returned: %x\n", hr);
     ok(bytes == sizeof(DWORD), "Returned bytes: %u, should be 4\n", bytes);
     ok(value == FALSE, "Return value: %u, should be 0\n", value);
-    property.Set = GUID_DMUS_PROP_XG_Hardware;
+    S(U(property)).Set = GUID_DMUS_PROP_XG_Hardware;
     hr = IKsControl_KsProperty(control_synth, &property, sizeof(property), &value, sizeof(value), &bytes);
     ok(hr == S_OK, "IKsControl_KsProperty returned: %x\n", hr);
     ok(bytes == sizeof(DWORD), "Returned bytes: %u, should be 4\n", bytes);
@@ -88,7 +88,7 @@ static void test_dmsynth(void)
     hr = IDirectMusicSynthSink_QueryInterface(dmsynth_sink, &IID_IKsControl, (LPVOID*)&control_sink);
     ok(hr == S_OK, "IDirectMusicSynthSink_QueryInterface returned: %x\n", hr);
 
-    property.Set = GUID_DMUS_PROP_SinkUsesDSound;
+    S(U(property)).Set = GUID_DMUS_PROP_SinkUsesDSound;
     hr = IKsControl_KsProperty(control_sink, &property, sizeof(property), &value, sizeof(value), &bytes);
     ok(hr == S_OK, "IKsControl_KsProperty returned: %x\n", hr);
     ok(bytes == sizeof(DWORD), "Returned bytes: %u, should be 4\n", bytes);