This is the dumbest OP of reddit. u/Umlautica did here BY FAR the best suggestion and this is the ONLY thing where the OP don't reply to that he will try it. Why not OP? You don't want to believe u/Umlautica ? Measurements don't lie, switch the wires and check it out!
And Cambridge Audio should be ashamed with the CXA81, what an terrible device, how can you make such an mistake...
But as worse as Cambridge Audio: Stereophile is absolutetly terrible too with their conclusion in the end that the CXA81 "performed well on the test bench". How dare they to say that after they just concluded that the polarity is mixed for the inputs, that makes the device unusable and not perfoming well at all, it performs terrible for that reason! Are they NUTS at Stereophile?