ok it looks like it has an incorrect extension then, it is probably really a .ra file. dont worry about trying to change the extension though, it won't do anything.
some real audio files are difficult to convert, it looks like you may have to use our soundtap software and record the file as you play it. get more information here: http://www.nch.com.au/soundtap/index.html
or you can use recordpad, but you need to know how to set it up properly: http://www.nch.com.au/recordpad/index.html