@rick_n You are 100% correct. New DAC or a new digital cable is not going to overcome the shortcomings of an untreated/balanced listening space.
The most critical audio component is the room. You can keep spending more money on better equipment and only get a fraction of the benefit because the room problems will eat up the rest.
Active bass traps will go a long, long way to elevate the sound presentation in the room and many are very inconspicuous. Also, in NY vernacular, if you have a TV between the speakers well, Forgeddaboutit.