diff --git a/phsource/ph_vietnam b/phsource/ph_vietnam
index d23db54c..017705e8 100644
--- a/phsource/ph_vietnam
+++ b/phsource/ph_vietnam
@@ -62,7 +62,8 @@ phoneme a
 	IF nextPh(N) OR nextPh(c) THEN
 	FMT(vnasal/a_n)
 	ELSE
-	FMT(vietnam/a)  //a_4)
+	//FMT(vietnam/a)  //a_4)
+	FMT(vietnam/a_x)
 	ENDIF
 endphoneme
 
diff --git a/phsource/vietnam/a_x b/phsource/vietnam/a_x
new file mode 100644
index 00000000..ceb43126
Binary files /dev/null and b/phsource/vietnam/a_x differ