"I've heard "Cleft chin, devil within" [being] said before" is another way of putting it.
It's not a common construction. It's two past participles in a row. The first relates to the subject, and the second to the object. The second past participle can sometimes be seen as an adjective.
"I've heard this Mass sung before; This Mass I've heard sung before"
"She's seen many hearts broken; Many hearts she's seen broken."
Student or Learner