some people love the sex but dont make a sound,
my boyf is the same but i know he likes it, you'll know if he wants it more, when we first dated 6 year ago i was like am i doing it right you arent making a noise i thought to myself, but after a while you'll know.
if he didnt like it he would change position
Sometimes people aren't as free and open in the beginning. My fiance was always really quiet but as time went on he became more comfortable. Tell him what you want. Say I like to hear you or tell him what turns you on. But perhaps you aren't compatible in that sense.
Pinch him. Works every time! :)
I am the same way as your bf. My wife is vocal but I am not unless I am receiving oral sex. But when I am having intercourse I do not make a lot of noise because I am consentrating on making her feel good. The more moans she makes the more I keep doing what I am doing. When she gets less vocal I switch up what I am doing.
So maybe he is just trying to do his best to please you and is so focused on it that his sounds take a back seat.
I would tell him that you would like to be more vocal. I was the same way with my boyfriend in the beginning. He likes a lot of noise and dirty talk sometimes, and it just takes a while to get used to! After a year and a half I do it very naturally now, but it took me a looooong time for it to be second nature. Just let him know it turns you on when you know he's feeling good and making noise :)