It's hard to know where to start. You don't need clones of the same button, to start. Multiple instances of the same button would make things much simpler. You would use instance variables to store anything unique to that button, and use the same code to do all the same things, just with the various instance variables.
Event 2 should be inside the "On start of layout" - it's creating 8 BeatSprites every tick!
I see what you are trying to do now. You've got your work cut out for you. You are going to have to calculate the bpm of the samples you already have and try to sync them all together. That's going to take some work, and a good understanding of the math.