For unknown reasons, AVM limits the FRITZ!Box Internet Radio stations lists (Heimnetz -> Mediaserver -> Internetradio) to max. 40 entries (FRITZ!OS v06.30). This snippet adds further stations to the list. Just adjust four lines below, then copy all, paste and execute in your browsers console.

addInternetRadioStation.js

/**
 * For unknown reasons, AVM limits the FRITZ!Box Internet Radio stations lists
 * (Heimnetz -> Mediaserver -> Internetradio) to max. 40 entries 
 * (FRITZ!OS v06.30).
 * 
 * This snippet adds further stations to the list. Just adjust four lines below,
 * then copy all, paste and execute in your browsers console.
 * 
 * function sendData taken from 
 * https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Forms/Sending_forms_through_JavaScript#Building_an_XMLHttpRequest_manually
 */

(function sendData() {

  var sid =     '1234567890123456';                           // <== Set to current Fritz!Box session ID 

  var data = {
    
    SrcId:      40,                                           // <== Set to current length of your internet radio stations list, increment if repeated
    src_name:   'Radio station name goes here',               // <== Adjust radio station name
    src_url:    'http://radio.station/stream/url/goes/here',  // <== Adjust radio station stream url

/* No need to change anything below this line */

    src_fon_cnt: 0,
    src_fon_cnt_all: 6,
    newSrc: 1,
    back_to_page: '/dect/internetradio.lua',
    SrcType: 'ir',
    btn_save:''
  };

  /* function sendData taken from 
     https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Forms/Sending_forms_through_JavaScript#Building_an_XMLHttpRequest_manually */

  var XHR = new XMLHttpRequest();
  var urlEncodedData = "";
  var urlEncodedDataPairs = [];
  var name;

  // We turn the data object into an array of URL encoded key value pairs.
  for(name in data) {
    urlEncodedDataPairs.push(encodeURIComponent(name) + '=' + encodeURIComponent(data[name]));
  }

  // We combine the pairs into a single string and replace all encoded spaces to 
  // the plus character to match the behaviour of the web browser form submit.
  urlEncodedData = urlEncodedDataPairs.join('&').replace(/%20/g, '+');

  // We define what will happen if the data is successfully sent
  XHR.addEventListener('load', function(event) {
    alert('Yeah! Data sent and response loaded.');
  });

  // We define what will happen in case of error
  XHR.addEventListener('error', function(event) {
    alert('Oups! Something goes wrong.');
  });

  // We setup our request
  XHR.open('POST', '/dect/source_edit.lua?sid=' + sid);

  // We add the required HTTP header to handle a form data POST request
  XHR.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
  // XHR.setRequestHeader('Content-Length', urlEncodedData.length);

  // And finally, We send our data.
  XHR.send(urlEncodedData);
})();