I solved that problem with a Schiit Kara preamp, but any good quality passive preamp will work. I simply run the output of my Microzotl pre into an input. In passive mode the volume control acts as an inline attenuator. I set mine about 2 o'clock which gives me enough room on my preamp volume control. It sounds better than the attenuator on my power amp. And it's easy to open the Kara full and essentially remove it from the chain.
An added bonus is conveniently switching to the SS mode of the Kara for casual listening.