I couldn’t read this post- But- the answer is simple. Reverse the speaker cables to your speakers. Simple and easy. By the way when you become a serious listener you will buy a preamp with a “ phase inversion” switch.
Phase inverting preamps
Apologies in advance for this newbie question. I was reading some reviews of preamps and a couple said that the preamp "inverts phasing" and that this would have to be accounted for elsewhere in the system. I know what phasing means, but how and where does one allow for it elsewhere in the system?