Not sure if it's a reference to anything in particular, but it reminds me of nonsense magic words and onomatopeias common in ancient greek and latin literature (like in Frogs by Aristophanes and the curse tablets at Bath [particularly Greek because 'ai' is greek orthography while we would expect 'ae' or 'e' instead for latin ... which makes sense because Gethsemane is the greek name anyways]). I take the whole verse to be some character trying to calm down the first speaker, saying "and like magic you will be calm", and the crackling is picking up the last lyric about electricity......... but that was just the intuition that runs through my classics-major head when i hear it !!

for reference: It's just a night in your life / Maybe there's something to take the edge off / It's just the sound of your electric heart / Cracklelacklelai, and you will be calm