Yes I have, now reverse the direction on your jumper and see if it sounds better one way than the other. Then dip the ends in a contact enhancer. Take the same wire strip the insulation and put it in an oversize silicone air tube. You have a direction, you have the best insulator you have the best contact surface. I think you are up to 10.00 usd. NOW let it settle. :-)
There are ways to make it sound even better.. Strip a piece of OCC and do the same thing.. Use Solid core vs stranded vs large strand or small strand. They ALL sound different in an air tube and one direction vs the other.. Do one speaker at a time. I always start on the left and work clockwise if there is more than 2 speakers.
Regards