diff --git a/dictsource/vi_rules b/dictsource/vi_rules
index 0ddd5ec8..d38b0184 100644
--- a/dictsource/vi_rules
+++ b/dictsource/vi_rules
@@ -892,7 +892,7 @@ ỵ	ỵ
 .group ô
         ô          o
         ôi         oI
-        ông        o#        // ông sound
+        ông        o#N        // ông sound
 ?2      ôi         O-        //south dialect 
         ôc		   o#k
  
@@ -900,7 +900,7 @@ ỵ	ỵ
 .group ồ
         ồ          o2
         ồi         oI2
-        ồng        o#2
+        ồng        o#N2
 ?2      ồi         O-2       
         
  
@@ -910,7 +910,7 @@ ỵ	ỵ
 .group ố
         ố          o3
         ối         oI3
-        ống        o#3
+        ống        o#N3
 ?2      ối         O-3       
         ốc		   o#3k
  
@@ -920,7 +920,7 @@ ỵ	ỵ
 .group ổ
         ổ          o4
         ổi         oI4
-        ổng        o#4
+        ổng        o#N4
 ?2      ổi         O-4       
         
  
@@ -930,7 +930,7 @@ ỵ	ỵ
 .group ỗ
         ỗ          o5
         ỗi         oI5
-        ỗng        o#5
+        ỗng        o#N5
         
  
 ?2      ỗi         O-5
@@ -940,7 +940,7 @@ ỵ	ỵ
 .group ộ
         ộ          o6
         ội         oI6
-   //     ộng        o#6
+        ộng        o#N6
 ?2      ội         O-6       
         ộc         o#6k
  
diff --git a/phsource/ph_vietnam b/phsource/ph_vietnam
index 9d23359d..64115226 100644
--- a/phsource/ph_vietnam
+++ b/phsource/ph_vietnam
@@ -598,7 +598,8 @@ phoneme o# // ông
 	ELSE
 	length 200
 	ENDIF
-  FMT(vnasal/a#u_n)
+  //FMT(vnasal/a#u_n)
+    FMT(vietnam/o#)
 endphoneme
 
 phoneme O# // ong
diff --git a/phsource/vietnam/V_2 b/phsource/vietnam/V_2
index 076fdc7b..f6d29a39 100644
Binary files a/phsource/vietnam/V_2 and b/phsource/vietnam/V_2 differ
diff --git a/phsource/vietnam/a_2 b/phsource/vietnam/a_2
index d8509abb..27b8c6a7 100644
Binary files a/phsource/vietnam/a_2 and b/phsource/vietnam/a_2 differ
diff --git a/phsource/vietnam/o# b/phsource/vietnam/o#
new file mode 100644
index 00000000..06d420dc
Binary files /dev/null and b/phsource/vietnam/o# differ