diff --git a/ThirdParty/fdk-aac/README.md b/ThirdParty/fdk-aac/README.md
index 3e644c9f5..66c79719d 100644
--- a/ThirdParty/fdk-aac/README.md
+++ b/ThirdParty/fdk-aac/README.md
@@ -8,7 +8,7 @@ https://github.com/mstorsjo/fdk-aac.git
 
 Using the following commandline:
 
-env CFLAGS="-arch x86_64 -arch arm64 -fPIC -isysroot $(xcode-select -p)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -mmacosx-version-min=10.12" CXXFLAGS="-arch x86_64 -arch arm64 -fPIC -isysroot $(xcode-select -p)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -mmacosx-version-min=10.12" LDFLAGS="-arch x86_64 -arch arm64 -mmacosx-version-min=10.12" ./configure --prefix=$(COG_REPO_DIR)/ThirdParty/fdk-aac
+env CFLAGS="-Os -arch x86_64 -arch arm64 -fPIC -isysroot $(xcode-select -p)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -mmacosx-version-min=10.12" CXXFLAGS="-Os -arch x86_64 -arch arm64 -fPIC -isysroot $(xcode-select -p)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -mmacosx-version-min=10.12" LDFLAGS="-arch x86_64 -arch arm64 -mmacosx-version-min=10.12" ./configure --prefix=$(COG_REPO_DIR)/ThirdParty/fdk-aac
 make -j8
 make install