R.J.
In my limited experience with autism ... I've come to learn it can really be anything. A person laughs too loud and gets put on the terror list for days/months. A person is known to come and go gets met with tears as if they're dying. A person is fond of a color/ perfume/ whatever and wears it... can prompt a meltdown. Crazy hair when it's usually neat, touching a beloved object (that may or may not be apparently special... my cousin "owns" all the doorknobs in the house that are glass... no one may touch them or he reacts the same way my son react if someone is breaking one of his beloved toys, anything can literally set someone on the spectrum off IF it happens to be their quirk... because it's about how they are perceiving events or sensory stimuli, as opposed to how the event actually happens. No matter if it's awful or not to US, it's awful to THEM.
Therapists can usually work with you to find ways to cope with those quirks (my cousin's doorknobs got the royal treatment : being taken OFF of doors was a nightmare... they absolutely had to be left on, but how to open doors? 2nd knobs that weren't glass. But it took MONTHS to figure out what the problem was to begin with (at first it was thought people coming/ going (he'd leap and hold onto them sobbing and pleading don't don't don't, then once it was narrowed down to a knob issue it took a LONG time how to figure out a way that let my aunt and uncle and other cousins live THEIR lives in a normal way without causing HIM anguish.)