I was trying to sum up a long story - to expand:
I had to put the Devialet on the 2.4GHz band to get it to work with my Roon Core on Ethernet, but the dropouts were horrendous (same experience I’ve had with other products on the 2.4GHz band). When the Devialet was on 5GHz and the Roon Core on ethernet they did not see each other. This is the first time that happened to me - did not have that issue with the Desktop or my Auralic Aries.
When I put the core back on my desktop and made them both have the same 5GHz WiFi band, all dropouts ended and I’ve had no issues since. Funny thing is that I had to switch my Auralic Aries (headphone setup) to a different 5GHz band as it started experiencing dropouts when sharing the same 5GHz band as the Devialet. My router is tri band (one 2.4GHz band and two 5GHz bands).