Items inside GridView getting repeated when screen scrolls

It's normal that you see the same items as you scroll down the GridView because in the getView method you set the drawables for the ImageView only when the convertView is null(for example for the first elements that are seen when the GridView appear on the screen). If the convertView is not null, meaning you have a recycled row view, you don't set the correct image and you remain with the image that was previously set on this recycled view. Try to modify the getView method like this:

public View getView(int position, View convertView, ViewGroup parent) {
    View v;
    if (convertView == null) {  // if it's not recycled, initialize some attributes
        LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(     Context.LAYOUT_INFLATER_SERVICE );
        v = inflater.inflate(R.layout.gridview_item_layout, parent, false);
    } else {
        v = (View) convertView;
    }
    TextView text = (TextView)v.findViewById(R.id.grid_item_text);
    text.setText(mTextIds[position]);
    ImageView image = (ImageView)v.findViewById(R.id.grid_item_image);
    image.setImageDrawable(mThumbIds[position]);
    return v;
}

Clicking an element shows you the correct items because you use the position parameter to retrieve the data.

These is my code for GirdView with Button + Textview

public View getView(final int position, View convertView, ViewGroup parent) {
        LayoutInflater mInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.grid_item, null);  
        } else {
            holder = (ViewHolder) convertView.getTag();
        }
        TextView text = (TextView)convertView.findViewById(R.id.texto_grid);
        text.setText(app_listaActiva_NOMBRES[position]);
        Button image = (Button)convertView.findViewById(R.id.miniatura_grid);
        image.setBackgroundResource(R.drawable.custom_button);
        image.setOnClickListener(new MyOnClickListener2(position,app_listaActiva_SONIDOS));
        return convertView;
    }