Square room doesn't help the situation. Change what you can, speaker placement, acoustic panels, rugs furniture room treatments, seating location. Here's a good article for understanding room acoustics; https://realtraps.com/art_room-setup.htm#:~:text=THE%2038%20PERCENT%20RULE,-The%20placement%20method&text=This%20offers%20the%20best%20compromise,back%20from%20the%20front%20wall.
Speakers sound too bright.
I just bought a new pair of Martin Logan 60xti speakers. They are too bright and fatiguing. I would like to avoid returning them. I've tried toeing them in and out. I cant get them further than 1ft away from the wall (back of speaker to wall). I have a about 1-2 hrs of play time on them. Not sure if break in will help settle the upper frequencies down. Any suggestions...?