I really think that people should communicate in a relationship. If he's not getting you off and he doesn't know it, he can't change it. You don't necessarily have to tell him outright that he's not doing the job because you are right, that'll probably hurt his feelings, but perhaps you can encourage him to 'do new things' with you that you know you'll like more, or if the pair of you are still active in the solo department you could tell him that you discovered something you liked and you'd enjoy sharing that with him. Slowly you could train him to do things that are more likely to excite you.