Conversion of crdownload files to mp3 file format

Unfortunately there seems to be no way how you could reliably recover the audio from the unfinished download, you most likely just need to download the file again and wait till the download is finished and the extension changed from crdownload back to mp3. You can try to manually rename crdownload back to mp3 and hope for at least partial playback, but in most cases it will be corrupted heavily.

Open CRDOWNLOAD file    Open MP3 file