This is the cable you need for running PRIME or Ableton Live from your headphone jack. Click goes Left, Loops go Right.
Looptimus Foot Controller
USB MIDI Foot Controller for Live Performance. Designed for Ableton Live, MainStage, Prime and more. 9 buttons, 20 banks, 16 channels, Expression Jack, Program Changes, MIDI Notes, All-access mode, PAD mode.