diff --git a/src/com/android/phone/CallWaitingSwitchPreference.java b/src/com/android/phone/CallWaitingSwitchPreference.java
index 01dd3b2..609488c 100644
--- a/src/com/android/phone/CallWaitingSwitchPreference.java
+++ b/src/com/android/phone/CallWaitingSwitchPreference.java
@@ -6,28 +6,34 @@
 import android.content.Context;
 import android.os.Handler;
 import android.os.Message;
+import android.os.PersistableBundle;
 import android.preference.SwitchPreference;
+import android.telephony.CarrierConfigManager;
 import android.telephony.TelephonyManager;
 import android.util.AttributeSet;
 import android.util.Log;
 
 import com.android.internal.telephony.Phone;
 
-import java.util.concurrent.Executor;
 import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Consumer;
 
 public class CallWaitingSwitchPreference extends SwitchPreference {
     private static final String LOG_TAG = "CallWaitingSwitchPreference";
+    private static final int DELAY_MILLIS_FOR_USSD = 1000;
     private final boolean DBG = (PhoneGlobals.DBG_LEVEL >= 2);
 
     private final MyHandler mHandler = new MyHandler();
     private Phone mPhone;
     private TimeConsumingPreferenceListener mTcpListener;
-    private Executor mExecutor;
+    private ScheduledExecutorService mExecutor;
     private TelephonyManager mTelephonyManager;
     private boolean mIsDuringUpdateProcess = false;
     private int mUpdateStatus = TelephonyManager.CALL_WAITING_STATUS_UNKNOWN_ERROR;
     private int mQueryStatus = TelephonyManager.CALL_WAITING_STATUS_UNKNOWN_ERROR;
+    private boolean mUssdMode = false;
 
     public CallWaitingSwitchPreference(Context context, AttributeSet attrs, int defStyle) {
         super(context, attrs, defStyle);
@@ -45,9 +51,14 @@
             TimeConsumingPreferenceListener listener, boolean skipReading, Phone phone) {
         mPhone = phone;
         mTcpListener = listener;
-        mExecutor = Executors.newSingleThreadExecutor();
+        mExecutor = Executors.newSingleThreadScheduledExecutor();
         mTelephonyManager = getContext().getSystemService(
                 TelephonyManager.class).createForSubscriptionId(phone.getSubId());
+        CarrierConfigManager configManager = getContext().getSystemService(
+                CarrierConfigManager.class);
+        PersistableBundle bundle = configManager.getConfigForSubId(phone.getSubId());
+        mUssdMode = (bundle != null) ? bundle.getBoolean(
+                CarrierConfigManager.KEY_USE_CALL_WAITING_USSD_BOOL, false) : false;
 
         if (!skipReading) {
             Log.d(LOG_TAG, "init getCallWaitingStatus");
@@ -67,7 +78,23 @@
     private void updateStatusCallBack(int result) {
         Log.d(LOG_TAG, "updateStatusCallBack: CW state " + result + ", and re get");
         mUpdateStatus = result;
-        mTelephonyManager.getCallWaitingStatus(mExecutor, this::queryStatusCallBack);
+        if (mUssdMode) {
+            Log.d(LOG_TAG, "updateStatusCallBack: USSD mode needs to wait 1s since Framework"
+                    + " has the limitation");
+            Consumer<Integer> resultListener = this::queryStatusCallBack;
+            try {
+                mExecutor.schedule(new Runnable() {
+                    @Override
+                    public void run() {
+                        mTelephonyManager.getCallWaitingStatus(mExecutor, resultListener);
+                    }
+                }, DELAY_MILLIS_FOR_USSD, TimeUnit.MILLISECONDS);
+            } catch (Exception e) {
+                Log.d(LOG_TAG, "Exception while waiting: " + e);
+            }
+        } else {
+            mTelephonyManager.getCallWaitingStatus(mExecutor, this::queryStatusCallBack);
+        }
     }
 
     @Override