diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2decf950..360ff716 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -10,7 +10,7 @@ if(MINGW)
 	message(FATAL_ERROR "Cannot currently build with MinGW")
 endif()
 
-set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake)
+set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake;${CMAKE_MODULE_PATH})
 include(vgmstream)
 
 # Options
diff --git a/ext_libs/CMakeLists.txt b/ext_libs/CMakeLists.txt
index af8c7be5..15892a94 100644
--- a/ext_libs/CMakeLists.txt
+++ b/ext_libs/CMakeLists.txt
@@ -1,3 +1,5 @@
+set(VGMSTREAM_EXT_INCLUDES ../ext_includes)
+
 if(MSVC)
 	if(USE_MPEG)
 		add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/libmpg123-0.lib ${CMAKE_CURRENT_BINARY_DIR}/libmpg123-0.exp
@@ -7,8 +9,8 @@ if(MSVC)
 		add_custom_target(libmpg123
 			DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/libmpg123-0.lib
 			SOURCES
-				${CMAKE_SOURCE_DIR}/ext_includes/fmt123.h
-				${CMAKE_SOURCE_DIR}/ext_includes/mpg123.h)
+				${VGMSTREAM_EXT_INCLUDES}/fmt123.h
+				${VGMSTREAM_EXT_INCLUDES}/mpg123.h)
 	endif()
 
 	if(USE_VORBIS)
@@ -16,8 +18,8 @@ if(MSVC)
 			COMMAND lib
 			ARGS /def:${CMAKE_CURRENT_SOURCE_DIR}/libvorbis.def /machine:x86 /out:${CMAKE_CURRENT_BINARY_DIR}/libvorbis.lib
 			DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libvorbis.def)
-		file(GLOB OGG_HEADERS "${CMAKE_SOURCE_DIR}/ext_includes/ogg/*.h")
-		file(GLOB VORBIS_HEADERS "${CMAKE_SOURCE_DIR}/ext_includes/vorbis/*h")
+		file(GLOB OGG_HEADERS "${VGMSTREAM_EXT_INCLUDES}/ogg/*.h")
+		file(GLOB VORBIS_HEADERS "${VGMSTREAM_EXT_INCLUDES}/vorbis/*h")
 		add_custom_target(libvorbis
 			DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/libvorbis.lib
 			SOURCES
@@ -34,7 +36,7 @@ if(MSVC)
 			DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libg7221_decode.def)
 		add_custom_target(libg7221_decode
 			DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/libg7221_decode.lib
-			SOURCES ${CMAKE_SOURCE_DIR}/ext_includes/g7221.h)
+			SOURCES ${VGMSTREAM_EXT_INCLUDES}/g7221.h)
 	endif()
 
 	if(USE_G719)
@@ -44,7 +46,7 @@ if(MSVC)
 			DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libg719_decode.def)
 		add_custom_target(libg719_decode
 			DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/libg719_decode.lib
-			SOURCES ${CMAKE_SOURCE_DIR}/ext_includes/g719.h)
+			SOURCES ${VGMSTREAM_EXT_INCLUDES}/g719.h)
 	endif()
 
 	if(USE_FFMPEG)
@@ -64,10 +66,10 @@ if(MSVC)
 			COMMAND lib
 			ARGS /def:${CMAKE_CURRENT_SOURCE_DIR}/swresample-vgmstream-3.def /machine:x86 /out:${CMAKE_CURRENT_BINARY_DIR}/swresample.lib
 			DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/swresample-vgmstream-3.def)
-		file(GLOB AVCODEC_HEADERS "${CMAKE_SOURCE_DIR}/ext_includes/libavcodec/*.h")
-		file(GLOB AVFORMAT_HEADERS "${CMAKE_SOURCE_DIR}/ext_includes/libavformat/*.h")
-		file(GLOB AVUTIL_HEADERS "${CMAKE_SOURCE_DIR}/ext_includes/libavutil/*.h")
-		file(GLOB SWRESAMPLE_HEADERS "${CMAKE_SOURCE_DIR}/ext_includes/libswresample/*.h")
+		file(GLOB AVCODEC_HEADERS "${VGMSTREAM_EXT_INCLUDES}/libavcodec/*.h")
+		file(GLOB AVFORMAT_HEADERS "${VGMSTREAM_EXT_INCLUDES}/libavformat/*.h")
+		file(GLOB AVUTIL_HEADERS "${VGMSTREAM_EXT_INCLUDES}/libavutil/*.h")
+		file(GLOB SWRESAMPLE_HEADERS "${VGMSTREAM_EXT_INCLUDES}/libswresample/*.h")
 		add_custom_target(ffmpeg
 			DEPENDS
 				${CMAKE_CURRENT_BINARY_DIR}/avcodec.lib
@@ -92,7 +94,7 @@ if(MSVC)
 			DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libatrac9.def)
 		add_custom_target(libatrac9
 			DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/libatrac9.lib
-			SOURCES ${CMAKE_SOURCE_DIR}/ext_includes/libatrac9.h)
+			SOURCES ${VGMSTREAM_EXT_INCLUDES}/libatrac9.h)
 	endif()
 
 	if(USE_CELT)
@@ -104,7 +106,7 @@ if(MSVC)
 			COMMAND lib
 			ARGS /def:${CMAKE_CURRENT_SOURCE_DIR}/libcelt-0110.def /machine:x86 /out:${CMAKE_CURRENT_BINARY_DIR}/libcelt-0110.lib
 			DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/libcelt-0110.def)
-		file(GLOB CELT_HEADERS "${CMAKE_SOURCE_DIR}/ext_includes/celt/*.h")
+		file(GLOB CELT_HEADERS "${VGMSTREAM_EXT_INCLUDES}/celt/*.h")
 		add_custom_target(libcelt
 			DEPENDS
 				${CMAKE_CURRENT_BINARY_DIR}/libcelt-0061.lib
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index e4d8dcad..b5a8da01 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -5,10 +5,10 @@ file(GLOB LAYOUT_SOURCES "${CMAKE_CURRENT_SOURCE_DIR}/layout/*.c")
 file(GLOB META_HEADERS "${CMAKE_CURRENT_SOURCE_DIR}/meta/*.h")
 file(GLOB META_SOURCES "${CMAKE_CURRENT_SOURCE_DIR}/meta/*.c")
 set(EXT_HEADERS
-	${CMAKE_SOURCE_DIR}/ext_includes/clHCA.h
-	${CMAKE_SOURCE_DIR}/ext_includes/pstdint.h)
+	${CMAKE_CURRENT_SOURCE_DIR}/../ext_includes/clHCA.h
+	${CMAKE_CURRENT_SOURCE_DIR}/../ext_includes/pstdint.h)
 set(EXT_SOURCES
-	${CMAKE_SOURCE_DIR}/ext_libs/clHCA.c)
+	${CMAKE_CURRENT_SOURCE_DIR}/../ext_libs/clHCA.c)
 file(GLOB MAIN_HEADERS "${CMAKE_CURRENT_SOURCE_DIR}/*.h")
 file(GLOB MAIN_SOURCES "${CMAKE_CURRENT_SOURCE_DIR}/*.c")
 
@@ -42,6 +42,7 @@ setup_target(libvgmstream)
 # Set up the proper include directories
 target_include_directories(libvgmstream PRIVATE
 	${CMAKE_CURRENT_SOURCE_DIR}
+	${CMAKE_CURRENT_SOURCE_DIR}/../ext_includes
 	coding
 	layout
 	meta)