Speakers sound too bright.

How very disappointing for me go on a really good rant about the wrong speakers! 
 

Your csbles if using a usb cable try the 

Cardas clear cable co 

Around $400 

Or less AQ Coffee

Just a reminder/info for everyone.  The OP has a pair of Martin Logan Motion series speakers.  These are typical box speakers with a folded Heil style tweeter. They are not the electrostatics that Martin Logan is better known for.

@rwalsh07 "What did you have before the Lintons?"

Let’s see: Bose 901 Series I and IV, Infinity 1001a, Infinity Column II, Infinity Monitor 2A, Infinity RS 2.5, Infinity Renaissance 80, Triangle Celius, Triangle Antals, Magnepan MMG, Magnepan .7, Tekton Perfect Set 2-12, Tekton Perfect Set 15, Moth Audio Cicadas, KEF LS-50s, Klipsch Heresy, M-L Electro Motion ESL, and some others 

I know purists would shudder to think that anyone serious about sound quality would stoop so low as to do this but this could be dealt with via EQ. turn down the treble and see if it solves the problem. Its a cheap and easy fix. If you cannot eq out the harshness you are hearing then its time to box em up and get something different.