diff --git a/stepmania/src/GameManager.cpp b/stepmania/src/GameManager.cpp
index 7e197a75cf..1d577b1369 100644
--- a/stepmania/src/GameManager.cpp
+++ b/stepmania/src/GameManager.cpp
@@ -1238,6 +1238,7 @@ void GameManager::SwitchNoteSkin( CString sNewNoteSkin )
 	{
 		CStringArray as;
 		GetNoteSkinNames( as );
+		ASSERT( !as.empty() );
 		SwitchNoteSkin( as[0] );
 	}
 	else