Asymmetric Room

I would start with covering the TV.

@gdnrbob   
Bob, thanks. Possibly. Doesn’t explain the frequency sweep issues on 2 specific frequencies. I do think I have a problem. Thanks
@knock1 Thanks. Did not fix the issue, but did sound darker. Any elegant solutions for covering the TV, I am all ears. 
 

Eliminating all toe in helped with glare, but not as precise instrument placement. Still searching. Thanks 

For a control, select a vocal cut that should be well-recorded recently - but seems to have distortion.*   Then proceed with many experiments to locate the cause of the distortion.  (This can take several days.)

A few suggestions: (1) throw a wool blanket over the coffee table in front of the listening position (2) unplug any HT gear - leaving only 2 channel powered (3)  make sure that power cords aren’t touching or paralleling any signal cables (4) confirm that all cable connectors are firmly plugged in - including AC plugs (5) mark the speaker positions with tape, then radically change their location - not just the toe-in (6) any other experiments. 

Good luck!

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* Years ago, when I had a similar issue, I selected Patty Griffin’s song, ’Let Him Fly’.   Some of her high notes were painful to my ears.  Now, they’re smooth as silk.   

In my case, the solution was clean power - with special attention to the streaming head end - modem/router/access point.  YMMV

"Any elegant solutions for covering the TV, I am all ears."

Quilt.

As @knock1 mentioned, a quilt will help with the TV reflection. You can buy a 1" dowel rod and cut it to the width of your TV. Drape 5-6" over the dowel and tack or sew it. When you want to listen to music, slip the quilt covered dowel over the top edge of the TV so the quilt is covering the TV. When you want to watch TV, lift it out and drop it below. Works really well...