Android MMAdView not displaying properly in S3?

Question

Hi every one I am using MMAdView in one of my applications, it is working fine in all Devices Except SAMSUNG S3, why this happen, have any idea of this issue.

Here an attached Screen short

this 480x800 Htc Device

And here Samsung s3 device 720x1280

IN samsung s3 device white space in right side corner.

This is the code I am using.

Activity code

public class MainActivity extends Activity { 

private static final int MED_BANNER_WIDTH = 480;
private static final int MED_BANNER_HEIGHT = 60;

//Constants for phone sized ads (320x50)
private static final int BANNER_AD_WIDTH = 320;
private static final int BANNER_AD_HEIGHT = 50;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main); 

    Log.i("MainActivity", "one");    

    int placementWidth = BANNER_AD_WIDTH;
    int placementHeight = BANNER_AD_HEIGHT;

    //Finds an ad that best fits a users device.
    if(canFit(BANNER_AD_WIDTH)) {
        Log.i("MainActivity", "two");
        placementWidth = BANNER_AD_WIDTH;
        placementHeight = BANNER_AD_HEIGHT;
    } else if(canFit(MED_BANNER_WIDTH)) {
        Log.i("MainActivity", "three");
        placementWidth = MED_BANNER_WIDTH;
        placementHeight = MED_BANNER_HEIGHT;
    }       

    MMAdView adView = new MMAdView(this);        
    adView.setApid("Appid");     
    MMRequest request = new MMRequest();         
    adView.setMMRequest(request);    
    adView.setId(MMSDK.getDefaultAdId());            
    adView.setWidth(placementWidth);
    adView.setHeight(placementHeight);

    //Calculate the size of the adView based on the ad size. Replace the width and height values if needed.
    int layoutWidth = (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, placementWidth, getResources().getDisplayMetrics());
    int layoutHeight = (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, placementHeight, getResources().getDisplayMetrics());

    //Create the layout parameters using the calculated adView width and height.
    RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(layoutWidth, layoutHeight);

    //This positions the banner.
    layoutParams.addRule(RelativeLayout.ALIGN_PARENT_TOP);
    layoutParams.addRule(RelativeLayout.CENTER_HORIZONTAL);

    adView.setLayoutParams(layoutParams);
    adView.getAd();     
    Log.i("MainActivity", "four");

    RelativeLayout layout = (RelativeLayout) findViewById(R.id.adBannerRelativeLayout);
    //Add the adView to the layout. The layout is assumed to be a RelativeLayout.
    layout.addView(adView);
}

protected boolean canFit(int adWidth) {

    Log.i("MainActivity", "five");
    int adWidthPx = (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 
            adWidth, getResources().getDisplayMetrics());
    DisplayMetrics metrics = this.getResources().getDisplayMetrics();
    Log.i("MainActivity", " metrics==> "+ metrics);
    return metrics.widthPixels >= adWidthPx;
}
 }

This is Xml file

      <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:mm="http://millennialmedia.com/android/schema"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content" >

<RelativeLayout
    android:id="@+id/adBannerRelativeLayout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

</RelativeLayout>

EDIT: this is the documentation that I am using MMAdView