diff --git a/apps/app_fax.c b/apps/app_fax.c
index c5d0f514bb..d9b0a3586f 100644
--- a/apps/app_fax.c
+++ b/apps/app_fax.c
@@ -20,6 +20,8 @@
 	<replacement>res_fax</replacement>
 ***/
 
+/* Needed for spandsp headers */
+#define ASTMM_LIBC ASTMM_IGNORE
 #include "asterisk.h"
 
 #include <string.h>