diff --git a/src/p_lnspec.cpp b/src/p_lnspec.cpp
index 9c93ca15c..9b38e149b 100644
--- a/src/p_lnspec.cpp
+++ b/src/p_lnspec.cpp
@@ -2587,6 +2587,7 @@ FUNC(LS_Line_SetBlocking)
 		ML_BLOCKUSE,
 		ML_BLOCKSIGHT,
 		ML_BLOCKHITSCAN,
+		ML_SOUNDBLOCK,
 		-1
 	};