I used to use Alpha Core IC's exclusively throughout my system. My experience with Alpha Core cables is that they need little break-in, if any. Also, they are a bit unique in that since they don't use a shield (and break-in is minimal) their connection orientation is not critical. I believe that the company addressed the speaker roll-off problem with an inductive link incorporated directly into the loudspeaker cable. Do your speaker cables have the inductors and are you sure the value is appropriate for your system?
Rgds, John
Rgds, John