diff --git a/panda/src/audio/Sources.pp b/panda/src/audio/Sources.pp
index c19b08a207..8d2a726280 100644
--- a/panda/src/audio/Sources.pp
+++ b/panda/src/audio/Sources.pp
@@ -1,5 +1,6 @@
 #define OTHER_LIBS dtool
 #define DIRECTORY_IF_AUDIO yes
+#define DIRECTORY_IF_IPC yes
 // #define USE_MIKMOD yes
 
 #begin lib_target