Aragorn was not surprised that Faramir was surprised.
“Yes. I am older than I look.”
"I've heard much about you," Faramir said slowly.
Aragorn was surprised at that. He did not expect Denethor to have spoken of him to his sons, and while the records in the archives mentioned his service, and detailed the battle against the corsairs, it was just as much as they would do for any captain of Gondor, Faramir included.
“There is a song,” Faramir explained, "Captain Thorongil and the Corsairs."