I never thought i'd like er, make noise or anything. But I do, a bit! And it's not forced. Sometimes just the physical exertion can make you 'make noise'. Failing that, breathe heavier? It's kind of discouraging for a guy because they look from a response from you to know that it's nice for you (in my experience), so like above posters have said, maybe experiment with a different position or something that is more pleasurable for you rather than laying there musing about how quiet it is.