Here are three ways to say the same thing. I wonder if there are particular rules regarding to the position of adverb phrases:
Then play those passages over and over again in your memory
Or,
Then play those passages in your memory over and over again
Or,
Then play over and over again those passages in your memory
I think the last is the worst choice but the first twos seem ok. The first is better because "over and over again" is closer to "play" so it is emphasized. Agreed?