diff --git a/iax.conf b/iax.conf
index e4c31b8..83e655d 100644
--- a/iax.conf
+++ b/iax.conf
@@ -150,7 +150,7 @@ bandwidth=low
 ; specific codecs.  Use "all" to represent all formats.
 ;
 disallow=all
-allow=alaw
+allow=gsm
 ;disallow=g723.1
 ;disallow=lpc10
 ;allow=gsm