I had problem extracting MP3 from FLV from this web-site with Replay Media Catcher. I received an error that there were no MP3 frames found.
You may also try to use other software that can extract MP3 files from FLV files. Or you can use an audio/video converter instread. I was able to convert FLV to MP3 with Media Catcher, for example.


And you can always record audio in MP3 format with direct sound recording software. Such programs can record any sound produced by your sound card.