I also have the M-Audio Fastrack Pro and just installed Linux Mint 17 on my lap top i can get it to play back through the sound card fine but trying to get it set up in ardour3 to record any sound is a different story alltogether has been a headache Linux is nothing like Windows when setting up audio software/hardware the thing that i noticed is that in the sound options it's doesn't let you select a different input like in Windows.
I read 'envy24ctrl' could solve my problem but I didnt find it ro download. I plug instruments and microfone but it doesnt send any signal to Ardour.
The M-audio interface works well in playback, but it doesnt work for recording. I use an M-Audio Fastr Track Pro, Jack and Ardour.