RAX8 dropping wired Ethernet connection randomly

My internet service is from Charter/Spectrum, via cable modem. As far as I can tell, only my wired TV is telling me my connection is periodically/intermittently and randomly dropping.

I first called Charter for support. They promptly said what I’d expect, we are seeing no issues. Upon some debugging steps, they asked me to contact the router manufacturer for support. I asked, how do we know this is a router issue vs a service or cable modem issue? No clear answer.

My TV is a Samsung, model UN43MU630D. It is connected by Ethernet, a CAT6 cable. I did network self tests and it claims it all checks out good. The message I get is on top of the TV screen, a banner that “Internet Disconnected” and very quickly after “Internet Connected”.

How do I determine if any other equipment is “seeing” interruptions? How to ID if the TV is the culprit or rule it out? Any other thoughts? This could be a blip that certain devices don’t see and the TV does. Not sure. Thanks.