I have had this happen twice in a few weeks, with two new buyers, and totally different items, so I guess it is a new scam going the rounds.
Now everything I sell is checked/ tested before listing, and then again when sent.
In two cases, one with a load of DVD films, and one with a phone & charger, the buyers have claimed the items don't work, and wanted a refund, without returning the items . In the first case, the buyer stated in their email "I want a refund, no questions, just refund. no I am not returning them."
and the second (the phone) wanted a refund claiming the phone didn't work, and I said I was sorry, I had tested it before sending, had they double-checked, tried charging, put a SIM in, etc, if none of that worked then please return it and I would give a refund within a few hours of getting it back - instantly, within minutes, they said they had found another charger that worked (interesting, considering I had tested all before sending, and only had the one compatible charger anyway, and this was a rare - for the UK- phone model so one is unlikely to have a compatible charger laying around, I would venture to say...) and that the phone was now working so clearly backing out of returning for refund. They left a negative saying not working though. (reported to ebid admins)
Now in any shop, or anything, you cant walk in, say and you want a refund for something without bringing the item back. I know that these items were certainly not faulty when they left my hands, and were appropriately packed. Granted some accident might happen in the post I guess, but then the same applies, I would have thought.
The once time I bought something online, and was not happy with it - I had no problem with returning the item to the seller, who also had no problem with the refund as long as the item was returned... and all went through reasonably.
It just seems interesting that this has surfaced recently twice over. Both times with new buyers (though I am still not blocking new buyers from my listings, I have a lot of new buyers and most are fine) I have been selling here for a reasonable while now, and on ebay since 2003, and not seen this apparent scam, until this winter.
I am not sure about seller protection on this one, other than responding truthfully to any negs received (something like "tested, working when sent. Offered buyer refund if item returned, buyer refused to return" or words to that effect,) leaving appropriate feedback (at least here, you can. I almost never leave negs, but this is an exception!) and reporting to admin.