Asymmetric Room

I have a semi treated asymmetric room & am getting some hash/glare from certain artists. I performed a frequency sweep from Qobuz using “Audio Line-Up Test Tones (Calibration Reference Check)”. I am getting a wavering tone in the 1khz and 1.25khz range.

chatGPT made several recommendations… speaker toe in, seating placement, ceiling treatment & treatment of the pool table on the left side (open area of the room). I can’t change seating position (large L shaped couch) & toe in had no effect. I very much prefer not to treat the ceiling (but will if I have to). 

My system & room layout is loaded. Any recommendations would be appreciated. Thanks