Tap the floating Play button to start the audio attached to the song. The button label becomes Pause. Tap again to pause. Once a track has been started for a set list, the button stays green.
Press and hold Play to open Select audio track.
If the pad files are not on the device yet, download them from the same dialog or from Audio Tracks.
On the set list, Autoplay media can start that audio for you: Never, With Autoscroll, or Always.
A pedal or touch zone can Toggle Backing Track, Play Backing Track, Pause Backing Track, Stop Backing Track, or Restart Backing Track.