diff --git a/conf/vars.xml b/conf/vars.xml
index 24e3f9a4ba..59e47c7968 100644
--- a/conf/vars.xml
+++ b/conf/vars.xml
@@ -84,7 +84,7 @@
        H264             - H.264 Video
 
   -->
-  <X-PRE-PROCESS cmd="set" data="global_codec_prefs=G722,PCMU,PCMA,GSM"/>
+  <X-PRE-PROCESS cmd="set" data="global_codec_prefs=G7221@32000h,G7221@16000h,G722,PCMU,PCMA,GSM"/>
   <X-PRE-PROCESS cmd="set" data="outbound_codec_prefs=PCMU,PCMA,GSM"/>
 
   <!--