Zoom disconnects only with Ethernet cable

My Zoom meetings disconnect after 5-some minutes on my MBA only when wired to Ethernet cable (which works perfectly when not Zooming). WiFi works fine, but I need the stability of a cable now. . After the disconnect, you must restart laptop, sign in again, and same issue repeat itself (over and over). A bit at a loss here (no expert). Pretty sure one little thing to adjust somewhere. The Zoom Error is 104102, something about unstable internet (not the case here), firewall (Zoom has access from MBA), proxy settings (above this guy's IQ level). Others have mentioned the "Switch". Suggestions? Thank you!