"Yep, that was the first thing I checked. This has really baffling."
I meant to say, "Yep, it was the first thing I checked and my speakers were OK. This is really baffling." Sorry about that.
My NAD and the ZTOL40 are sitting on the floor in between and parallel to the speakers, and not on the rack. The ZTOL40 is an LTA demo amp and it is well broken in. For A/B comparisons, I swapped cables and interconnects. I'm using Blue Jean speaker cables with locking banana plugs and Transparent Super RCA interconnects.
I spent most of my time listening to my regular playlists. Everything works fine with the ZTOL, not so much anymore with the NAD. This evening, I'll start experimenting again with speaker positions.
I plan to keep the rack, but move it to the back of my left side wall. But, first I have to do a little remodeling. Funny thing, I had several contractors scheduled to give me estimates when this crazy virus mess started. I've since put that project on hold.