Cables to settle brightness

The amount of contradictory answers on this thread is mesmerizing.

Yes, you can cure (to a point) brightness by swapping cables, but I would first try a different DAC and see if things get better. Then eventually fine-tune with cables. It makes me laugh when I read "do not use cables as tone controls". Cables have a sound, and you pretty much cannot do without them, so they have to be taken into consideration when you voice a system. It is those who consider cables as mere physical connections without any sonic personality who have it all wrong, and good luck to them achieving what they want.

Kubala Sosna Emotion. Warm

Do you have optical ethernet isolation to your DAC? If not I would definitely look into that. It removed a fatiguing bright scrim that I suffered with for years. I have a Sonore optcalRendu going to an ultraDigital to I2S on my PS Audio Directstream, and I replaced all the switch mode power supplies with linear,

I'm willing to bet that it isn't your cables or your DAC. It is noise. And it isn't really bright as much as it is brittle, like fingernails on a chalkboard in the middle of the high end. You don't hear it specifically until it isn't there and you go back to your prior configuration. It'll be either power-line noise or source/transmission noise coming through your router or switch (or both). In my experience, filtering or fixing one or both will provide noticeable results.

@bondmanp I second how do you know its not the DAC? What was your original Digital chain you mention?  I use Sonore along with many others and have zero issues with treble. I have Be tweeters in my Sorpras. So if it was going to be bright they would show it.

for the OP I agree do not use Silver. Tried my Ver1 Nordost Blue Heavens and I hated them with these speakers. Cardas now and I love them. I have the PowerPlant 20 with everything plugged into it.as well. No harshness at all. Stay copper. I use Audioquest Mckenzie for interconnects.