Ah...update on the Blue Aura's I'd been using for one of my side surrounds.
Turns out the (2.4Ghz) wireless signal from it interferes with Logitech (dongle and BT) keyboards and trackball and the NUC I7, so I had to remove it.
Which makes me wonder about the other 2.4Ghz wireless adapters mentioned here.
Still waiting (well, have given up, really) on WISA.
Fortunately, wires are only a problem for on location, so can deal with it.