diff --git a/third_party/build/gsm/libgsmcodec.dsp b/third_party/build/gsm/libgsmcodec.dsp
index 872cbf0..f7ca6f0 100644
--- a/third_party/build/gsm/libgsmcodec.dsp
+++ b/third_party/build/gsm/libgsmcodec.dsp
@@ -42,7 +42,7 @@
 # PROP Target_Dir ""
 F90=df.exe
 # ADD BASE CPP /nologo /W3 /GX /O2 /D "WIN32" /D "NDEBUG" /D "_MBCS" /D "_LIB" /YX /FD /c
-# ADD CPP /nologo /W1 /GX /O2 /I "." /I "../../gsm/inc" /D "WIN32" /D "NDEBUG" /D "_MBCS" /D "_LIB" /YX /FD /c
+# ADD CPP /nologo /MT /GX /O2 /I "." /I "../../gsm/inc" /D "WIN32" /D "NDEBUG" /D "_MBCS" /D "_LIB" /YX /FD /c
 # ADD BASE RSC /l 0x409 /d "NDEBUG"
 # ADD RSC /l 0x409 /d "NDEBUG"
 BSC32=bscmake.exe
@@ -66,7 +66,7 @@
 # PROP Target_Dir ""
 F90=df.exe
 # ADD BASE CPP /nologo /W3 /Gm /GX /ZI /Od /D "WIN32" /D "_DEBUG" /D "_MBCS" /D "_LIB" /YX /FD /GZ /c
-# ADD CPP /nologo /W2 /Gm /GX /ZI /Od /I "." /I "../../gsm/inc" /D "WIN32" /D "_DEBUG" /D "_MBCS" /D "_LIB" /YX /FD /GZ /c
+# ADD CPP /nologo /MTd /W2 /Gm /GX /ZI /Od /I "." /I "../../gsm/inc" /D "WIN32" /D "_DEBUG" /D "_MBCS" /D "_LIB" /YX /FD /GZ /c
 # ADD BASE RSC /l 0x409 /d "_DEBUG"
 # ADD RSC /l 0x409 /d "_DEBUG"
 BSC32=bscmake.exe