Digital streamer signal issue with ethernet vs wifi

I have put up a couple post recently since I have been away for a few years and just now getting back into this and completely new at the streaming option. You all have been very helpful and I really appreciate it. I just bout a Node 2i about 2 weeks ago and I am loving it so far. 30 day test going on of both Qobuz and Tidal. My issue is with connection. I set the Node 2i up originally to use my wifi 5gh connection, new Asus AC3100 and it sounded fine. Since the system is down a floor from where my router is the signal can be a little weak at times. So per Bluesounds advice I connected it via ethernet. Now this is done via ethernet port wall jack being my system which I installed 8 years when our home was being built using Cat 5e. Last night I was comparing the 2 as I thought I believed wifi sounded better. So I was doing a little A/B comparison last night. Using Alison Krauss, a very low key song with a lot of AK vocal, Forget about it album, song Empty Hearts and also Norah Jones, come away with me. When using the ethernet cable I was getting some faint distortion in the vocal, like a static radio station. I checked both Tidal and Qobuz, same. When I switched back to wifi and cleared the cache of the Node 2i, it was perfectly fine. After reading some John Darko article and suggestions posted by the likes of Aurilac I can only assume my ethernet cable is injecting some noise somewhere.  Am I missing something? I mean I am fine with wifi and did maximize some 5 ghz channel settings for better signal. We are out in the country so there is not much wifi traffic, in fact Netspot app said my 5ghz was the only one in the area, rest were 2.4