Thanks PRC. I'm sure that's it but I'm still missing something. 

So I'm going to ramble on here, subjecting the list to my failures.

- I did have Blackhole installed; I uninstalled it and rebooted but still no dice. Haven't used Airplay recently but I do remember its annoying propensity to show up as default.

Here's my probe:

hamilr4-mbp15:Desktop hamilr4$ chuck --probe

[chuck]: found 2 device(s) ...

[chuck]: ------( audio device: 1 )---------------

[chuck]: device name = "Apple Inc.: MacBook Pro Microphone"

[chuck]: probe [success] ...

[chuck]: # output channels = 0

[chuck]: # input channels  = 1

[chuck]: # duplex Channels = 0

[chuck]: default output = NO

[chuck]: default input = YES

[chuck]: natively supported data formats:

[chuck]:   32-bit float

[chuck]: supported sample rates:

[chuck]:   44100 Hz

[chuck]:   48000 Hz

[chuck]:   88200 Hz

[chuck]:   96000 Hz

[chuck]: 

[chuck]: ------( audio device: 2 )---------------

[chuck]: device name = "Apple Inc.: MacBook Pro Speakers"

[chuck]: probe [success] ...

[chuck]: # output channels = 2

[chuck]: # input channels  = 0

[chuck]: # duplex Channels = 0

[chuck]: default output = YES

[chuck]: default input = NO

[chuck]: natively supported data formats:

[chuck]:   32-bit float

[chuck]: supported sample rates:

[chuck]:   44100 Hz

[chuck]:   48000 Hz

[chuck]:   88200 Hz

[chuck]:   96000 Hz

So if I run the pitch-track.ck example (timeless) and print out target_freq near the end of the main while loop, I'll see fluctuating output as expected when run in mini-audicle. Nothing in terminal.

I'm trying:

chuck --adc0 --in1 pitch-track.ck

or 

chuck --adc:0 --in:1 --srate:48000 pitch-track.ck

or to be more explicit...

chuck --adc:0 --in:1 --dac:0 --out:2 --srate:48000 pitch-track.ck

(both should work right? i.e. colon or no-colon)

and just get a wall of:

0.000000 :(float)

0.000000 :(float)

0.000000 :(float)

0.000000 :(float)

from Terminal, vs. the expected:

46.875000 :(float)

93.750000 :(float)

46.875000 :(float)

93.750000 :(float)

93.750000 :(float)

plus sweet sine-waves in MiniAudicle. 

Interestingly enough, MiniAudicle only shows my output devices under Device Browser > Audio Interfaces (i.e. MacBook Pro Speakers here). Can't remember if it always only showed output and not input?