diff --git a/src/java/com/android/ims/ImsCall.java b/src/java/com/android/ims/ImsCall.java
index 5fceb7a..1d728a1 100644
--- a/src/java/com/android/ims/ImsCall.java
+++ b/src/java/com/android/ims/ImsCall.java
@@ -1652,6 +1652,7 @@
             // Make a copy of the current ImsCallProfile and modify it to enable RTT
             Parcel p = Parcel.obtain();
             mCallProfile.writeToParcel(p, 0);
+            p.setDataPosition(0);
             ImsCallProfile requestedProfile = new ImsCallProfile(p);
             requestedProfile.mMediaProfile.setRttMode(ImsStreamMediaProfile.RTT_MODE_FULL);
 
@@ -3101,6 +3102,7 @@
         public void callSessionRttModifyRequestReceived(ImsCallSession session,
                 ImsCallProfile callProfile) {
             ImsCall.Listener listener;
+            logi("callSessionRttModifyRequestReceived");
 
             synchronized(ImsCall.this) {
                 listener = mListener;
@@ -3125,6 +3127,7 @@
         public void callSessionRttModifyResponseReceived(int status) {
             ImsCall.Listener listener;
 
+            logi("callSessionRttModifyResponseReceived");
             synchronized(ImsCall.this) {
                 listener = mListener;
             }
diff --git a/src/java/com/android/ims/ImsManager.java b/src/java/com/android/ims/ImsManager.java
index ad8d11b..6fc1292 100644
--- a/src/java/com/android/ims/ImsManager.java
+++ b/src/java/com/android/ims/ImsManager.java
@@ -1635,6 +1635,28 @@
         }
     }
 
+    public void setRttEnabled(boolean enabled) {
+        try {
+            setAdvanced4GMode(enabled || isEnhanced4gLteModeSettingEnabledByUser());
+            final int value = enabled ? ImsConfig.FeatureValueConstants.ON :
+                    ImsConfig.FeatureValueConstants.OFF;
+            Thread thread = new Thread(() -> {
+                try {
+                    Log.i(ImsManager.class.getSimpleName(), "Setting RTT enabled to " + enabled);
+                    getConfigInterface().setProvisionedValue(
+                            ImsConfig.ConfigConstants.RTT_SETTING_ENABLED, value);
+                } catch (ImsException e) {
+                    Log.e(ImsManager.class.getSimpleName(), "Unable to set RTT enabled to "
+                            + enabled + ": " + e);
+                }
+            });
+            thread.start();
+        } catch (ImsException e) {
+            Log.e(ImsManager.class.getSimpleName(), "Unable to set RTT enabled to " + enabled
+                    + ": " + e);
+        }
+    }
+
     /**
      * Set the TTY mode. This is the actual tty mode (varies depending on peripheral status)
      */