Another Mesh Connection Issue or is it?

Hello All Fellow Sonotians !! I have a fairly substantial Sonos system (12 devices on S2) with a fairly substantial mesh network all in a fairly substantial (5000+ sqft) home. I have 6- EERO 6+ spread throughout 2 adjacent structures (main Home and shop).  I have 2- isp here both xfinity gig plus, and an Att fiber 1 gig.  To reel back For years I had the older Eero 2nd gen, spread over here as well as only xfinity. Life was grand Sonos was seamless. Never skipping, never missing a beat. EERO stopped updating the older routers so I removed these and replaced with the 6 plus units. Life was still ok so I thought , the music was fine at night or on the weekends. I noticed it started to skip more and more frequently… so I called in xfinity and had the lines checked thinking sure I’m perhaps loosing speed at peak intervals… well all was as good as could be.. I’m testing out well over 800mbps usually, at 4-5 pm on weekdays it drops off sharply so I call xfinity they say there is nothing they can do I have the fastest internet money can buy…  so I’m thinking to myself Sonos doesn’t need the speed it just needs a solid connection at best… so as my problem at my main home continues at the peak times like when I get home from work or on the weekends when I want to enjoy my music… i remember I have another property at a weekend home where I have some (4)  no longer supported Eero 2nd gen, running off a 300mb max budget Spectrum cable plan. This location has 4 Sonos products and they have been playing without a hiccup for years….  So my frustration begins to mount and I keep messing with my masterpiece of a main home Sonos system… back at home I get another isp to try, you know they all assure me the internet will not buffer at peak times… so I try the fiber 1gig. The problem is still prevalent almost exactly the same as with the xfinity. So now all this time and effort reading trying anything and I’m still at square one. I’m almost positive it has to do with my mesh network but I tried direc wiring a handful of my Sonos units to my1gb wired switch… it made it worse !! now so before I remove all my 6 plus Eero and try something else or even kick the Sonos to the curb someone talk me off the ledge ! I have always loved my Sonos but I can’t take much more ! Are my Eeros throttling me since Bezos bought them? They worked fine before Amazon got involved 😂… help guys 🍺🍺cheers and thanks in advance - and sorry for the ramble!