Just a thought, if I remember right the Kimber Hero is not a shielded cable, is that correct. Not a good idea to have those long cables hooked up only to the power amp and not connected to the preamp on the other end, I wouldn't push my luck with that test. If you have to have that long of an IC you might try a shielded pair.
This is from their web site.
http://www.kimber.com/Products/Interconnects/Hero/Hero_Spec.aspx
Jim
This is from their web site.
http://www.kimber.com/Products/Interconnects/Hero/Hero_Spec.aspx
Jim