Android org.xml.sax.SAXParseException:意外令牌

当我的应用程序从我的网站下载XML提要时，有时会获取它，Sametime会生成以下错误：

10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ org.xml.sax.SAXParseException:意外标记 位置：文本�������������}[oI…@1:87英寸 java.io。InputStreamReader@41f3b510 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 在 org.apache.harmony.xml.parsers.DocumentBuilderImpl.parseDocumentBuilderImpl.java:146 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 在 it.pucillo.sampo.infodisilvio.MyActivity$rss.doInBackgroundMyActivity.java:489 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 在 it.pucillo.sampo.infodisilvio.MyActivity$rss.doInBackgroundMyActivity.java:472 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 在android.os.AsyncTask$2.callAsyncTask.java:288 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 位于java.util.concurrent.FutureTask.runFutureTask.java:237 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 在android.os.AsyncTask$SerialExecutor$1.runAsyncTask.java:23110-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 在 java.util.concurrent.ThreadPoolExecutor.runWorkerThreadPoolExecutor.java:1112 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ 在 java.util.concurrent.ThreadPoolExecutor$Worker.runThreadPoolExecutor.java:587 10-15 12:26:33.295 28032-28372/it.pucillo.sampo.infodisilvio W/System.err﹕ java:841

这是我的异步任务的代码：

@Override
        protected String doInBackground(String... params) {
            try {

                URL url = new URL(feedUrl);
                HttpURLConnection conn = (HttpURLConnection) url.openConnection();
                conn.setConnectTimeout(30000);

                if (conn.getResponseCode() == HttpURLConnection.HTTP_OK) {
                    InputStream is = conn.getInputStream();
                    InputSource xs= new InputSource(is);

                    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
                    DocumentBuilder db = dbf.newDocumentBuilder();
                    Document document = db.parse(xs);
                    elementi = document.getDocumentElement();
                }

            } catch (Exception e) {

                e.printStackTrace();

            }
            return "Executed";
        }