Update advanced.php

scripts/advanced.php

@@ -310,9 +310,21 @@ foreach($formats as $format){
         this can be useful for earing impaired people.<br>
 
         <p style="margin-left: 40px">
-        Choose here the shifting tool, must be a value in the list { ffmpeg, sox }.<br>
+
       <label for="freqshift_tool">shifting tool: </label>
-        <input name="freqshift_tool" type="text" value="<?php print($newconfig['FREQSHIFT_TOOL']);?>" required/><br>
+      <select name="freqshift_tool">
+            <option selected="<?php print($newconfig['FREQSHIFT_TOOL']);?>"><?php print($newconfig['FREQSHIFT_TOOL']);?></option>
+      <?php
+        $formats = array("sox","ffmpeg");
+
+        $formats = array_diff($formats, array($newconfig['FREQSHIFT_TOOL']));
+      foreach($formats as $format){
+        echo "<option value='$format'>$format</option>";
+      }
+      ?>
+      </select>
+
+        Choose here the shifting tool.<br>
         </p>
 
         <p style="margin-left: 40px">