diff --git a/setup/win-ci.py b/setup/win-ci.py
index ae1160ee11..9ce0d555cc 100644
--- a/setup/win-ci.py
+++ b/setup/win-ci.py
@@ -86,6 +86,7 @@ def setup_env():
     os.environ['CI'] = 'true'
     os.environ['OPENSSL_MODULES'] = os.path.join(SW, 'lib', 'ossl-modules')
     os.environ['PIPER_TTS_DIR'] = os.path.join(SW, 'piper')
+    os.add_dll_directory(os.path.join(SW, 'ffmpeg', 'bin'))
 
 
 def main():