What happens to the pH of a buffer system if one halves the concentration of boht the acid and the salt?

Since an acid is made of a salt and water, disregard the water. If the concentration of the acid is less (pH more toward the neutral pH7) then it will take less buffer to mask the acid because it takes less to bring it from say pH 5 to pH7 and it would to bring a stronger acid, say pH2 to pH 7.