Heresy, but here goes: Devialet to Lumin?

[Confused]

I see, too, that you suggest a cable change.  I'll be thinking about that...

@Flashman
Yes, it seems rather boring and predictable, but I seconded @Hifi_swlon 's suggestion because changing speaker cables made an important difference in my own system. And I was surprised that it did what I wanted, but happily it was a $600.00 fix, rather than another fix with more zeros on the wrong side of the decimal. Not sexy, but on target.

I also think @Confused has a good point about the frequency range that may be relevant; the mids, rather than the treble. Listen to him, not me.

That's very kind Damon, but I like to think all voices and opinions should be heard and considered here!  Anyway, a point to note, I was not suggesting a boost to the mids.  Going back to the OP, it was mentioned that the system sounds "too digital".  I know some people get a little upset by the term "too digital" because it usually relates to things that have nothing to do with "digital" at all.  Digital, when implemented correctly, should simply sound pure and clean.  That said, I fully understand what people actually mean when they say something sounds "too digital" or "more analogue", and in my experience the "digital" sound tends to be prominence in the presence band, so the bit a little below the treble region, but a long way above the mids.  So maybe it is a small cut at about 5kHz, and a small boost at about 500Hz, that turns "digital sound" into "analogue sound".  (obviously this will be very system dependent)  Plus, this is easy enough to try if you have Roon's PEQ in your system.  Of course, it the issues can be cured without PEQ this is by far the better way to go, but PEQ is simple, and cost-free if you have Roon already, so I think it is worth spending an hour or so experimenting.