In Auto-Tune Pro and Auto-Tune Live, many parameters can be controlled in real time with any MIDI controller that sends MIDI CC (continuous controller) messages. You can make MIDI Control Assignments in the Preferences / Options menus of Auto-Tune Pro and Auto-Tune Live (respectively) or with your recording software's (DAW) plugin MIDI control features.
Commonly, DAWs have features that allow you to control plugins with MIDI CC messages. (For example, Logic Pro, Ableton Live, Studio One, Pro Tools, and many other DAWs have built-in MIDI CC assignment or "MIDI Learn" capabilities to control plugins).
If MIDI Control Assignment settings you configure within Auto-Tune Pro or Auto-Tune Live are not working, this may be because your DAW's plugin MIDI control feature is overriding Auto-Tune's MIDI Control Assignment settings.
In these situations we recommend you consult your DAW's manual or help pages to figure out how to use its MIDI features to control Auto-Tune with your MIDI controller. The procedure for routing MIDI to an audio plugin will vary depending on what DAW you are using, so please see your DAW’s manual or help pages for more information about how to do this.