You may have upper midrange sensitivity
You might try all the suggestions listed above. However...
I have listened to Martin Logan loudspeakers for years, but could not tolerate the bright sound they produced, which usually led to listening fatigue and headaches for me. Knowing that many people loved these speakers, I just assumed that I had a sensitivity to ML's upper midrange output.
Not too long ago, I listened to the Martin Logan Ascent i loudspeakers in a dealer's showroom using Primare equipment and Audioquest cables. I still found the sound to be bright and somewhat harsh, especially on brass instruments. I bought the speakers anyway.
When the Ascents were delivered to my home and I hooked them up to my Proceed AMP5, Klyne System 7 preamp, Musical Fidelity NuVista 3D CD player, and Transparent cables, I heard a very smooth, rich, and slightly warm sound right out of the box with no brightness or harshness whatsoever. For the first time in 20 years I was able to listen to a pair of MLs for three to four hours with no problems. (You can only imagine how happy I was!)
So you may need to change your electronics and cables if the other suggestions do not work for you.