The usual difficult-to-assist kind of description (sorry!). It goes along like this:

Na na na na na (ascending) na na na na na (descending, some noise plays after, electronic) (whole line is pretty quiet/subdued)
Na na na na (higher pitch, ascending) naaa (down a bit) (x2)

After about a few repeats (which get successively louder) there's some really heavy/electronically modified voice says something, a line or two I can't quite make out (suspect I'd have the answer if I did), and the non-speaking bit after that goes along like:
Na na na na na na na na na na (x2, quiet)
Na na na na na plays at the end of that

Yeah if you can work it out then you're either a lot smarter than the average individual or my description is actually good. PLEASE HELP IT'S DRIVING ME NUTS.