Threshold FET 10/e cartridge amp questions

I love the preamp, which is all-original, unmodified. The problems:

It just doesn't seem to have enough gain to work with a Shelter 501II and Threshold FET 10/e line amp: I have hum problems I don't have with my Heed Quasar. AFAIK the Threshold has one level of gain for MM's.

And: while the sound is really something, it's shy on bass and a bit bright by comparison to the Quasar. I am lucky to have "tone controls" of a sort with my Yamaha NS1000 driver level controls (I pulled the mids down about 2dB!) and my subwoofer gain (up a tad), but I recognize a workaround when I see it, LOL.

I can't report the current settings on the Threshold: getting it into and out of my rack is a real process. MM capacitance is supposed to be kind of immaterial anyhow, I believe. Maybe someone familiar with this unit can recommend ideal settings for the Shelter 501?

I do apologize to all: I mis-stated things*. I have an MM cart (Shelter 501II) and have the Threshold phono pre set for maximum gain. As to "noise": it's hum, really. There's no noise issue.

If anyone knows the best capacitance setting for a cart like the Shelter, it would be a big help

* At the risk of rationalizing/over-dramatizing things I'm 4 months out from a stroke and still have a lot to learn about how I can get things screwed up: I'm not used to it.

Thanks to all for your help! It's much appreciated.