The problem is that the Leben has abnormally low gain. Most MM phono stages offer around 40db of gain.
I have had the Leben in my system and quite frankly it is quite vague - not worth the money in my view. Even a cheapy Soundsmith phono at around $1k was significantly better.
My suggestion would be to get another phono stage or if you have the Leben, sell it and use the money for another phono.