Using a WiiM with an AVR is always going to have this sort of issue.This is exactly what I expect is the case so there's no point running analog from (any) Wiim to the AVR. The other (minor) issue is my AVR has no trigger in and I'm not sure if feeding a signal from the WiiM to either Digital or Analog inputs will wake up the AVR. I need to test this at some point but need to wait until I get my Ultra
Just FYI there are quite a few modern DAC/Amps that can detect signal over Digital circuits and auto-on as a result but I haven't seem any with an Analog equivalent. You need an old fashioned trigger input for this.
I'm running a WiiM Pro over Coax to a Topping MX3 and in celing B&W speakers in my kitchen for this reason. SQ isn't the highest priority here.