https://ecsdcards.com/common/plugins/RadEditorAjax/audio/audio.js

1//tool handler function
2Telerik.Web.UI.Editor.CommandList["audio"] = 
3//function name is not needed.
4function(commandName,editor,oTool)
5{
6    // RadEditor old version using editor.ShowDialog function
7    // RadEditor Ajax version using editor.showExternalDialog function
8    editor.showExternalDialog(
9        "/common/plugins/RadEditorAjax/audio/AudioRecorderRadAjax.aspx",null,400,340, 
10        //function that is executed when the dialog is closed with the return value.
11        //see Default.aspx file 
12        function(sender, returnValue)
13        {
14            if(returnValue)
15            {
16                editor.pasteHtml(returnValue);
17            }
18        },
19         null,
20        'Audio Recorder',
21        true,
22        Telerik.Web.UI.WindowBehaviors.Close + Telerik.Web.UI.WindowBehaviors.Move,
23        false,
24        true);        
25        
26};