Folks,
Over many years, there has been a small but steady history of similar complaints.
I am of the view that, in recent years, any ability of CASA to handle such matters in a fair and balanced way, has deteriorated, and it was never too flash in the first place.
A common source of such complaints, based on my experience, is a departing vindictive and vengeful ex-spouse or equivalent. Some of whom don't even seem to realise it will probably severely curtail their settlement.
Neighbors come next on the list. I have even seen two cases where the "complaint" was made by what turned out to be a disgruntled pilot or other cabin crew for the same airline.
Sadly, the easy answer, the easy way out, is to sacrifice the target. It is always a hard fightback from there.
Tootle pip!!