Index: CMake/Modules/FindOSS.cmake
--- CMake/Modules/FindOSS.cmake.orig
+++ CMake/Modules/FindOSS.cmake
@@ -4,11 +4,11 @@
 IF(UNIX)
   IF(CMAKE_SYSTEM_NAME MATCHES "Linux")
     SET(OSS_HDR_NAME "linux/soundcard.h")
-  ELSE(CMAKE_SYSTEM_NAME MATCHES "Linux")
-    IF(CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
+  ELSEIF(CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
       SET(OSS_HDR_NAME "sys/soundcard.h")
-    ENDIF(CMAKE_SYSTEM_NAME MATCHES "FreeBSD")
-  ENDIF(CMAKE_SYSTEM_NAME MATCHES "Linux")
+  ELSE()
+      SET(OSS_HDR_NAME "unknown")
+  ENDIF()
 ENDIF(UNIX)
 
 FIND_PATH(OSS_INCLUDE_DIR "${OSS_HDR_NAME}"
