VAC Phono in Avatar Super

I have a VAC Avatar Super with a phono stage that has 42 db of gain. I have a Benz Glider High Output cartridge at 2.5mV. The documentation says it is appropriate with phono stages with gain of 40db or more and I asked VAC about it before I purchased. I have to use more volume than with my CDP and at higher volumes there is a background hum that is noticeable in quiet passages. VAC sells an external MC step-up network that plugs into the MM input that I think is like $900. Given that I have a high output cart, would the VAC step-up be a mismatch? Would I be better off going with a seperate phono stage? Different cartridge? Any and all advice appreciated.