Krystal's theme appears within this excellent and calming cover of a classic Star Fox Adventures track.
Glitchy, dubsteppy Fox McCloud goodness.
The Smashified Team show us what might have been.
LucasJG1994 sends recordings, sheet music, and midi file for the hard-to-get Krystal Captured song from Star Fox Adventures.
liltommyj remixed Star Fox 64 SFX to create a song.
Two excellent Star Fox remix songs