Select your volca input to use it as a controller for all 8 voices. Tweak your sample as you wish within your sample2!
  "Round Robin" is better in general but "Active Note Count" should be better to create sequences. Give it a try
   NOTE: "Active Note Count" disables note-off and sustain pedal support
  Use this option if your sample default pitch is not in middle C's octave
  Enables/disables velocity sensitivity. Fixed velocity sends 127 (max value)
  With "Stereo" mode, lower notes are slightly panned to the left and higher notes to the right. "Mono" is just mono, no panning
  Change the amount of Reverb using REVERB MIX knob in your volca
  By default it detects note-off and sustain pedal and stops the sample at that point
  By default it populates the same sample for all velocities