Class D Amps Cable matter??

There is a small (about 1 percent) amount of the switching noise on the speaker cables. It can couple to anything else by capacitive or electromagnetic coupling. Capacitive you can reduce by keeping cables away or crossing cables at 90 degrees. Electromagnetic coupling is not very likely since switching frequency is most likely in order of 0.5MHz - equivalent to about 600m wavelength. Antenna becomes very ineffective below 1/10 of the wavelength - 60 meters.

I have Wireworld cables with my Class D Integrated amp. I submit they make a difference.

Mlapenta - my cables, Acoustic Zen Satori, were criticized for "full" lower midrange. It is perfect with my class D amp Rowland model 102 since it sounded lean with AQ cables. Now chestiness came back to male voices, cellos sound deeper etc.

Just because interconnects so rarely just start acting up, have you tried cleaning the connections on your amp and pre, or just swapping the interconnects? Worth a shot to possibly save some $, and many report improvements in their system's sound after cleaning connections (including speaker inputs) if you haven't done this recently.

As an aside, are you using any power conditioning? Unlike more conventional amps where conditioning can sometimes do more harm than good, my experience with "digital" amps has been that they sound better with power supplied by a good power conditioner. Anyway, best of luck in sorting out your interconnect issue.

Mlapenta - an exceptional cable in your price range is the gZero3 from KLE Innovations.

They are exceptionally good at defeating EMI/RFI and they sound amazing.

I use their cables throughout my system, including their digital spdif.

Take a look at their wed site for cable reviews - I've also provided some reviews on Audiogon also

Regards