To much bass, really


I have the Lehmann Black Cube SE II Phono Amp.
The problem is I'm getting way to much bass. I've played with the switches under the unit and to know avail.
Do I need to go inside the unit to adjust the bass?
My set ,Rega P5 , Dynavector 20x2 Low Moving Cartridge. 
Hopefully someone can help.
trip
Im not familiar with for owning one but did become curious enough to search up. 

" In addition Lehmann includes sixteen bass roll-off curves between 7Hz and 90Hz. If your speakers don’t have extended low frequency response this is a very useful feature that can save amplifier power for audible frequencies instead of wasting it on pointless woofer pumping. You are not likely to hear low frequency response differences if your speakers don’t go much below 60Hz but your amplifier will thank you.
Read more at http://www.analogplanet.com/content/lehmann-audio-black-cube-se-ii-mmmc-phono-preamp-reviewed#Lm92RQ...
I read this article. It doesn't really tell me how to adjust the bass. Unless I'm missing something. 
The manual is confusing. 
I'm not sure why you think it's your phono.

What exactly is your set up and what's your perception?

Best,

E