ListView Checkbox repeated every 4th items

I have a ListView that is filled with checkboxes. When I click on a checkbox, the 4th checkbox and its multiplications (8th, 12th, etc..) are also checked automatically without me clicking on them.

`public class CarActivity extends Activity implements DownloadResultReceiver.Receiver { private DownloadResultReceiver mReceiver; List items; String carNumber; private GoogleApiClient client;

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


    Bundle b = this.getIntent().getExtras();
    String url = b.getString("url");
    carNumber = b.getString("carNumber");
    String model = b.getString("model");
    final String category = b.getString("category");


    submit = (Button) findViewById(R.id.submit);

    submit.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view) {

            String url = null;
            if (category.equals("الأجهزة الطبية")) {
                url = "http://ift.tt/1P62Q3g";
            } else if (category.equals("الأفراد")) {
                url = "http://ift.tt/1qRfdok";
            } else if (category.equals("التدريب")) {
                url = "http://ift.tt/1P63Swb";
            } else if (category.equals("الصيانة الميكانيكية")) {
                url = "http://ift.tt/1qRfgAm";
            } else if (category.equals("الصيانة الطبية")) {
                url = "http://ift.tt/1P644vj";
            } else if (category.equals("المستلزمات الطبية")) {
                url = "http://ift.tt/1qRfLKR";
            } else if (category.equals("تجهيزات كابينة السائق")) {
                url = "http://ift.tt/1P640vo";
            } else if (category.equals("سجلات السيارة")) {
                url = "http://ift.tt/1qRf8AP";
            }

            new SubmitItems().execute(url);

        }
    });


    //getActionBar().setTitle("");
    //if (Connection.isConnectedToInternet(getApplicationContext())) {
    if (true) {
        /* Starting Download Service */
        mReceiver = new DownloadResultReceiver(new Handler());
        mReceiver.setReceiver(this);
        Intent intent = new Intent(Intent.ACTION_SYNC, null, this,
                DownloadService.class);

        /* Send optional extras to Download IntentService */
        intent.putExtra("url", url);
        String data = null;
        try {
            data = URLEncoder.encode("model", "UTF-8") + "=" + URLEncoder.encode(model, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        intent.putExtra("data", data);
        intent.putExtra("receiver", mReceiver);
        intent.putExtra("requestId", 101);
        startService(intent);
    } else {
        new AlertDialog.Builder(CarActivity.this)
                .setTitle("Oops")
                .setMessage("No Internet Connection!")
                .setPositiveButton("Ok",
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog,
                                                int id) {
                            }
                        }).show();

    }

    // ATTENTION: This was auto-generated to implement the App Indexing API.
    // See http://ift.tt/1Shh2Dk for more information.
    client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
}

@Override
public void onStart() {
    super.onStart();

    // ATTENTION: This was auto-generated to implement the App Indexing API.
    // See http://ift.tt/1Shh2Dk for more information.
    client.connect();
    Action viewAction = Action.newAction(
            Action.TYPE_VIEW, // TODO: choose an action type.
            "Car Page", // TODO: Define a title for the content shown.
            // TODO: If you have web page content that matches this app activity's content,
            // make sure this auto-generated web page URL is correct.
            // Otherwise, set the URL to null.
            Uri.parse("http://host/path"),
            // TODO: Make sure this auto-generated app deep link URI is correct.
            Uri.parse("android-app://com.example.khloud.qery/http/host/path")
    );
    AppIndex.AppIndexApi.start(client, viewAction);
}

@Override
public void onStop() {
    super.onStop();

    // ATTENTION: This was auto-generated to implement the App Indexing API.
    // See http://ift.tt/1Shh2Dk for more information.
    Action viewAction = Action.newAction(
            Action.TYPE_VIEW, // TODO: choose an action type.
            "Car Page", // TODO: Define a title for the content shown.
            // TODO: If you have web page content that matches this app activity's content,
            // make sure this auto-generated web page URL is correct.
            // Otherwise, set the URL to null.
            Uri.parse("http://host/path"),
            // TODO: Make sure this auto-generated app deep link URI is correct.
            Uri.parse("android-app://com.example.khloud.qery/http/host/path")
    );
    AppIndex.AppIndexApi.end(client, viewAction);
    client.disconnect();
}


class SubmitItems extends AsyncTask<String, String, String> {
    private ProgressDialog pDialog;

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pDialog = new ProgressDialog(CarActivity.this);
        pDialog.setMessage("Attempting submitting...");
        pDialog.setIndeterminate(false);
        pDialog.setCancelable(false);
        pDialog.show();
    }

    @Override
    protected String doInBackground(String... args) {
        String url = args[0];


        try {
            for (Item item : items) {
                String data = URLEncoder.encode("carNumber", "UTF-8") + "=" + URLEncoder.encode(carNumber, "UTF-8") + "&" +
                        URLEncoder.encode("itemName", "UTF-8") + "=" + URLEncoder.encode(item.getName(), "UTF-8") + "&" +
                        URLEncoder.encode("found", "UTF-8") + "=" + URLEncoder.encode(item.getFound() + "", "UTF-8") + "&" +
                        URLEncoder.encode("notFound", "UTF-8") + "=" + URLEncoder.encode(item.getNotFound() + "", "UTF-8") + "&" +
                        URLEncoder.encode("working", "UTF-8") + "=" + URLEncoder.encode(item.getWorking() + "", "UTF-8") + "&" +
                        URLEncoder.encode("notWorking", "UTF-8") + "=" + URLEncoder.encode(item.getNotWorking() + "", "UTF-8") + "&" +
                        URLEncoder.encode("notes", "UTF-8") + "=" + URLEncoder.encode(item.getNotes(), "UTF-8");
                Connection.getJSONfromURL(url, data);
            }

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (Exception e) {
            return null;
        }

        return "save Successfully";
    }

    protected void onPostExecute(String file_url) {
        pDialog.dismiss();
        if (file_url != null) {
            Toast.makeText(CarActivity.this, file_url, Toast.LENGTH_SHORT)
                    .show();
            finish();
        }

    }

}

@Override
public void onReceiveResult(int resultCode, Bundle resultData) {
    switch (resultCode) {
        case DownloadService.STATUS_RUNNING:
            break;
        case DownloadService.STATUS_FINISHED:
            String response = resultData.getString("result");
            if (response == null)
                Log.d("respooo", "null");
            intializeProcess(response);
            break;
        case DownloadService.STATUS_ERROR:
        /* Handle the error */
            String error = resultData.getString("error");
            Log.d("error", error);
            break;
    }
}


private void intializeProcess(String response) {
    Log.d("response", response);
    ItemsRetrieval itemRetrieval = new ItemsRetrieval();
    if (itemRetrieval.GetMainAPI(response)) {
        // load.setVisibility(View.GONE);
        items = itemRetrieval.getItems();

        Log.e("Items Size", items.size() + "");

        doWork();
        //getActionBar().setTitle(singer.getName());
        //getActionBar().setIcon(R.drawable.singer_icon);


    }
}

private void doWork() {
    populateListView();
    registerClickCallback();
}




private void populateListView() {
    ArrayAdapter<Item> adapter = new MyListAdapter();
    ListView list = (ListView) findViewById(R.id.items);
    list.setAdapter(adapter);
}

private void registerClickCallback() {
    ListView list = (ListView) findViewById(R.id.items);
    list.setOnItemClickListener(new AdapterView.OnItemClickListener() {



        @Override
        public void onItemClick(final AdapterView<?> parent, View viewClicked,
                                final int position, long id) {


            final Item item = items.get(position);


   ///////////////////////////////////




        }
    });





        }



///////////////////

private class MyListAdapter extends ArrayAdapter<Item> {


    public MyListAdapter() {
        super(CarActivity.this, R.layout.item, items);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // Make sure we have a view to work with (may have been given null)
        View itemView = convertView;
        if (itemView == null)
            itemView = getLayoutInflater().inflate(
                    R.layout.item, parent, false);


        Item item = items.get(position);

        TextView name = (TextView) itemView.findViewById(R.id.textView1);
        name.setText(item.getName());


        return itemView;
    }
}

} `