lstune seems to have trouble with certain devices. M-Audio Fast Track Pro and my integrated audio codec both output:
Codec: "audio/pcm"
Frequency: 8000
Frequency: 11025
Frequency: 22050
Frequency: 44100
Frequency: 48000
Sample size: 8
Sample size: 16
Sample size: 32
Sample type: 1
Sample type: 2
Sample type: 3
Device name "sysdefault:CARD=Pro"
Default audio format is not supported. Using nearest available
Channels: 1
Frequency: 8000
Codec: "audio/pcm"
Sample Size: 8
Only floats or 32/16 bit integer samples are supported! Exiting
Sample Type: 2
Both of these only have support for 24 bit in hardware. My Zoom H1 recorder, used as an audio interface, however also only supports up to 24 bits but works out of the box.
I was able to fix it by adjusting lines 108 and following in AudioIO.cc.