Cartridge output 1.0mv to 65db gain phono, problem?

I have used a 1mv (.9mv measured) cart with my 57.5 dB gain phono pre.  The result was ok for mid to high level listening.  The software of the digital gain control induced a gain curve at the lowest volume settings, as does your preamp, that increases the gain between steps to mimic an analog volume pot.  I could not adequately control the volume level - it was either too loud or too soft.  My pre has 120 steps while yours has 214.  That may or may not be enough help.