What? I really just looked at a past post of yours...
But anyway, sound genjutsu is strong against Uchihas because of, the chakra can't be seen by the Uchihas, sound genjutsu, could be used without the Uchiha even hearing it, because there are waves that the ear can't hear, but they can still affect the Uchiha because they're still infusing the chakra to make the genjutsu, the Uchiha won't notice that and won't know he is in a genjutsu, the other types are more visible, so the Uchiha could confirm he/she is in a genjutsu by checking his chakra flow, with Sound genjutsu, he probaly won't notice anything