I would still give it more time to burn in and settle before you start to change (even though I agree with (Bob_bundus), it migh be a "synergy" mismatch for you. If you decide to change ac cable as always if you have a chance to audition first it would be even more helpful, but try your more budget oriented change before a "heavier one" there's a lot of variabiles you're still working with. good luck and keep posting if you don't find it right off.
