Buffer Shuffler is a premium audio effect that comes with Max for Live. This official video from Ableton demonstrates how it works.
This audio effect “shuffles” incoming audio by buffering the audio, then replaying it in whatever order you’ve specified. Each channel of the stereo signal can be shuffled with different patterns (unlike Beat Repeat) and there is also a “dice” mode that randomizes the shuffle pattern at each bar crossing.
Finally, a smoothing setting limits the amount of clicking at each transition point. Use sensibly to add subtle variations or go full-on to see where it takes you.