Potential problem with sale.

I didn't see this possible dilema addressed in the archives. My question has to do with a product you sell being properly represented, no functional or comsmetic issues, but not being compatible with the buyer's system. Case in point-- I have recently sold a dvd player (Camelot) which when hooked up to the buyer's 16:9 tv (Panasonic) produces uneven blackbars when playing a 2.35:1 movie in progressive scan mode-thin bar at the top and a wider bar at the bottom. The buyer is going to trade his tv for a Mitsubishi tomorrow and hopefully this will be a non-issue. I had no problems with my Sony XBR2. What is my obligation to the buyer if the new tv performs in the same manner? Am I to let him return the player to me for refund? My opinion is that sales on Audiogon are final and not a trial of the equipment (if properly represented). I have good feedback, and wouldn't want that to change because of this transaction. I am interested in the views and opinions of other Audiogoners as to this situation. Thanks for your time and input.

Jeff Strossner