diff --git a/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerARPAPlusEnglishPhonemizer.cs b/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerARPAPlusEnglishPhonemizer.cs
index 7332b3bc9..5da60666a 100644
--- a/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerARPAPlusEnglishPhonemizer.cs
+++ b/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerARPAPlusEnglishPhonemizer.cs
@@ -2,9 +2,12 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Reflection;
 using System.Text;
 using OpenUtau.Api;
 using OpenUtau.Core.G2p;
+using OpenUtau.Core.Ustx;
+using Serilog;
 
 namespace OpenUtau.Core.DiffSinger {
     [Phonemizer("DiffSinger English+ Phonemizer", "DIFFS EN+", language: "EN", author: "Cadlaxa")]
@@ -37,25 +40,35 @@ public override Result Process(Note[] notes, Note? prev, Note? next, Note? prevN
                 throw new Exception("Result not found in the part");
             }
             var processedPhonemes = new List<Phoneme>();
+            var langCode = GetLangCode() + "/";
 
             for (int i = 0; i < phonemes.Count; i++) {
                 var tu = phonemes[i];
 
                 // Check for "n dx" sequence and replace it with "n"
                 // the actual phoneme for this is "nx" like (winner [w ih nx er])
-                if (i < phonemes.Count - 1 && tu.Item1 == "n" && phonemes[i + 1].Item1 == "dx") {
+                if (i < phonemes.Count - 1 && tu.Item1 == langCode + "n" && HasPhoneme(langCode + "n") && phonemes[i + 1].Item1 == langCode + "dx" && HasPhoneme(langCode + "dx")) {
+                    // If phoneme "n" and "dx" exist, process "n" and skip "dx"
+                    processedPhonemes.Add(new Phoneme() {
+                        phoneme = langCode + "n",
+                        position = tu.Item2
+                    });
+                    i++; // Skip next phoneme
+                } else if (i < phonemes.Count - 1 && tu.Item1 == "n" && HasPhoneme("n") && phonemes[i + 1].Item1 == "dx" && HasPhoneme("dx") && !HasPhoneme(langCode + "n") && !HasPhoneme(langCode + "dx")) {
+                    // If phoneme "n" and "dx" exist, but language-specific "n" and "dx" don't exist, process "n"
                     processedPhonemes.Add(new Phoneme() {
                         phoneme = "n",
                         position = tu.Item2
                     });
-                    // Skip the next phoneme ("dx")
                     i++;
                 } else if (ShouldReplacePhoneme(tu.Item1, prev, next, prevNeighbour, nextNeighbour, out string replacement)) {
+                    // If phoneme should be replaced, process the replacement
                     processedPhonemes.Add(new Phoneme() {
                         phoneme = replacement,
                         position = tu.Item2
                     });
                 } else {
+                    // If no conditions are met, just add the current phoneme
                     processedPhonemes.Add(new Phoneme() {
                         phoneme = tu.Item1,
                         position = tu.Item2
@@ -67,31 +80,44 @@ public override Result Process(Note[] notes, Note? prev, Note? next, Note? prevN
             };
         }
 
-        // Method to determine if a phoneme should be replaced based on specific conditions
         private bool ShouldReplacePhoneme(string phoneme, Note? prev, Note? next, Note? prevNeighbour, Note? nextNeighbour, out string replacement) {
             replacement = phoneme;
-            if (phoneme == "q") {
+            var langCode = GetLangCode() + "/";
+
+            if ((phoneme == langCode + "cl" || !HasPhoneme("q")) && HasPhoneme("vf")) {
+                if (!prevNeighbour.HasValue || string.IsNullOrWhiteSpace(prevNeighbour.Value.lyric)) {
+                    replacement = "vf";
+                    return true;
+                }
+            }
+            if ((phoneme == langCode + "q" || phoneme == "q") && HasPhoneme("vf")) {
+                if (!prevNeighbour.HasValue || string.IsNullOrWhiteSpace(prevNeighbour.Value.lyric)) {
+                    replacement = "vf";
+                    return true;
+                }
+            }
+            if ((phoneme == langCode + "q" || phoneme == "q") && HasPhoneme("cl")) {
                 replacement = "cl";
                 return true;
             }
-            if (phoneme == "q") {
-                // vocal fry the vowel is the prevNeighbour is null
-                if (!prevNeighbour.HasValue || string.IsNullOrWhiteSpace(prevNeighbour.Value.lyric)) {
-                replacement = "vf";
+            if (phoneme == langCode + "q" && !HasPhoneme("cl")) {
+                replacement = "q";
                 return true;
-                }
             }
-            // automatic relaxed consonants
-            if ((phoneme == "t" || phoneme == "d") && (nextNeighbour.HasValue && IsVowel(nextNeighbour.Value))) {
-                replacement = "dx";
+            if (phoneme == langCode + "q" && !HasPhoneme("cl") && HasPhoneme(langCode + "q")) {
+                replacement = langCode + "q";  // Keep the language-specific "q"
                 return true;
             }
-            return false;
-        }
-        // Method to check if a phoneme is a vowel
-        private bool IsVowel(Note note) {
-            string[] vowels = GetBaseG2pVowels();
-            return vowels.Contains(note.lyric);
+            if (phoneme == "ax" && !HasPhoneme("ax")) {
+                return true;
+            }
+            if (phoneme == langCode + "ax" && !HasPhoneme(langCode + "ax")) {
+                replacement = langCode + "ah";  // Replace language-specific "ax" with "ah"
+                return true;
+            }
+
+            return false; 
         }
+
     }
 }
diff --git a/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerG2pPhonemizer.cs b/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerG2pPhonemizer.cs
index c46c8ddd3..c1648c335 100644
--- a/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerG2pPhonemizer.cs
+++ b/OpenUtau.Core/DiffSinger/Phonemizers/DiffSingerG2pPhonemizer.cs
@@ -1,10 +1,11 @@
-using Serilog;
+using Serilog;
 using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 
 using OpenUtau.Api;
+using OpenUtau.Classic;
 
 namespace OpenUtau.Core.DiffSinger
 {
@@ -35,7 +36,12 @@ public abstract class DiffSingerG2pPhonemizer : DiffSingerBasePhonemizer
         //vowels and consonants of BaseG2p
         protected virtual string[] GetBaseG2pVowels()=>new string[]{};
         protected virtual string[] GetBaseG2pConsonants()=>new string[]{};
-        
+
+        private Dictionary<string, bool> phonemeSymbols = new Dictionary<string, bool>();
+        protected bool HasPhoneme(string phoneme) {
+            return phonemeSymbols.ContainsKey(phoneme);
+        }
+
         protected override IG2p LoadG2p(string rootPath, bool useLangId = false) {
             //Each phonemizer has a delicated dictionary name, such as dsdict-en.yaml, dsdict-ru.yaml.
             //If this dictionary exists, load it.
@@ -54,6 +60,13 @@ protected override IG2p LoadG2p(string rootPath, bool useLangId = false) {
                         var dictData = Yaml.DefaultDeserializer.Deserialize<DiffSingerG2pDictionaryData>(dictText);
                         g2pBuilder.Load(dictData);
                         replacements = dictData.replacementsDict();
+                        // Collect all symbols from the dictionary and add them to phonemeSymbols
+                        if (dictData.symbols != null) {
+                            foreach (var symbol in dictData.symbols) {
+                                phonemeSymbols[symbol.symbol.Trim()] = true;
+                            }
+                        }
+                        Log.Error("Loaded symbols: " + string.Join(", ", phonemeSymbols.Keys));
                     } catch (Exception e) {
                         Log.Error(e, $"Failed to load {dictionaryPath}");
                     }
@@ -70,7 +83,6 @@ protected override IG2p LoadG2p(string rootPath, bool useLangId = false) {
             if(baseG2p == null){
                 return new G2pFallbacks(g2ps.ToArray());
             }
-            var phonemeSymbols = new Dictionary<string, bool>();
             foreach(var v in GetBaseG2pVowels()){
                 phonemeSymbols[v]=true;
             }