Ocarina Input
The game's input manager polls the controller at a rate of ~60Hz. Ocarina input is handled separately from the common game input, and circumstances can cause it to be delayed into a different controller input window. When this happens, the input seen by the ocarina on a given frame may be different from that seen by the rest of the game.
This is a source of potential desyncs in macros, so when playing or recording a macro, The Practice ROM ensures that the ocarina input is the same as the common game input for any given frame.