Yes this ^^
Also some chickens are just shouters - that does not sound to me like there is anything wrong with her.
As well as what @LaFleche suggests you could also try various distractions. Mine will shut up for a bit when really intent on something. A hanging cabbage or a huge heap of...
Can you post a video so we can hear what it sounds like?
Also, you say physically healthy which is great - but how does she behave? Does she do normal chicken-ey things like dust bathing and scratching etc.
I have a hen that is very loud and shouts most of the time - I sort of just assumed she...