Hi Mark, It's just not possible to use any computer program to convert something as complex as - for example a WAV or MP3 Audio file, to a MIDI file. Trying to extract all the individual parts of a recording - say drums, bass, strings, brass, woodwind etc. and assign each instrument to a separate MIDI file tracks is just a dream!
Don't waste your time.....

Remember, MIDI files - unlike WAV and MP3 files, do not actually contain any musical 'Sounds' - they are merely a set of digital instructions which need to be fed to a software program on a PC such as Windows Media Player, or a device like a keyboard capable of interpreting the instructions and producing Audio from a built-in set of Digital Sound Samples.