"Refurb" has become an abbreviation for "inheriting the previous owner's problem". Nobody seems to be able/care enough to actually get to the root of the problem any longer.
We had a similar experience with our own TV a couple of years ago. Lucky for us, Costco took the thing back for credit following a second failed attempt to get the original rebadger (Westinghouse) to replace the thing under warranty.
I've seen this devolve over the last 10 years or so dealing with equipment repair at work. At some point, we turned in a broken HP DeskJet. 6 months later, as part of another service call swap, we got the first printer back exhibiting the same symptoms we orginally sent it back for.