diff --git a/stepmania/src/StepMania.vcproj b/stepmania/src/StepMania.vcproj
index d30541e9b8..64996e5c17 100644
--- a/stepmania/src/StepMania.vcproj
+++ b/stepmania/src/StepMania.vcproj
@@ -1913,6 +1913,12 @@ cl /Zl /nologo /c verstub.cpp /Fo"$(IntDir)"\
 			<File
 				RelativePath="RageSoundManager.h">
 			</File>
+			<File
+				RelativePath="RageSoundMixBuffer.cpp">
+			</File>
+			<File
+				RelativePath="RageSoundMixBuffer.h">
+			</File>
 			<File
 				RelativePath="RageSoundPosMap.cpp">
 			</File>