It seems Jaaziah is another son of Merari. And, Beno is the son of Jaaziah. Beno is mentioned twice because he is a leader in his family. However, some Bibles translate "Beno" as "his son" rather than as a proper name. Those Bibles read like this: "and from his sons, Jaaziah, his son ... from Jaaziah, his son: Shoham."