LCD-2 from 2011

What amp are you using? I'm using a Woo WA22 tube amp with my fazor LCD2s and don't have any glare.

I had a Burson Soloist solid state, but much prefer a tube amp with all my headphones.

I'm using a custom 12AU7/FET zero feedback amp designed by a brilliant designer/technician I work with frequently. I discovered that my tube selection, an RCA Clear Top, may have had something to do with it. It's smoother with a French military Radio Technique I got from Upscale Audio.

Older Audeze are notorious for having variations from one example to the next. That went on for many years until the more recent models, and I think they have it worked out by this point. But anything over a couple years old is likely to be pretty unique even compared to an "identical" headphone of the same type. It's luck of the draw whether you get one you like or not. 

That said you can definitely try to find synergy with rolling tubes or opamps or cables etc, that might help fine tune things to your liking. But if not, it's probably time to switch headphones if that aspect bothers you too much.

I got a used LCD-X, 2021 version. It's a good match for a DAC I have on hand for a trial period, the Gustard R26. My older DAC, a modifed Gustard x20pro, was pretty bright, so that could have emphasized the peakiness in the LCD-2. In any case I like the X/R26 combination better. The only thing is that the LCD-X is a little rolled off on the high end, and the R26 isn't good at presenting the highest frequency details such as hall ambience. Through my speakers (Spendor S3/5) the high end of the R26 sounds better, but the imaging is not good compared to my modified x20pro. I'm trying to figure out whether I want a more extended, spacious headphone than the LCD-X, or whether I should modify the R26 in some way (perhaps a reversible mod: get a good 10 MHz clock).