My Quicksilver preamp inverts polarity

Swap the cables at the speaker end.

At least half of CDs are inverted Polarity anyway so what’s the difference? You might actually be better off. 

Seriously, the polarity of CDs and LPs is around 50/50.I actually can notice polarity in many recordings.I have a switch at hand to flip.The difference is so small you need double platinum Golden Ears to care.
I remember one fellow I helped buy some equipment, who just could not live with an inverting amp he had, It BOTHERED HIM he had to reverse the speaker wires. So he sold it and bought a different amp.
When theory beats reality..