Dissapointed buyer, item malfunctions experience?

It's nice you all appear willing to refund payment and shipping immediately if something malfunctions after it has arrived at the buyer--but we are NOT dealers who have an obligation to refund and accept the unit back! I would file a claim with the shipping company or have the buyer get an estimate on repairs then offer to split the cost of repairs. But take the unit back, when it was fine when it left me? That's a risk buyers assume, I thought! At least that's what I have thought the couple of times I've had gear malfunction after buying it used on Audiogon. I knew I had to get it repaired; if it was a major repair I might ask the seller for help but he's really not obligated at all. Providing money back guarantee is not something I do or feel equipped to do. Anything can and has happened with FedEx, USPS, UPS etc.

Viridian, Squirrel et al., you are missing my point. I have never been anything less than reasonable and fair with anyone on this site and those who have bought from or sold to me can and have attested to that. My point simply is that Audiogon does NOT require sellers to act like retail dealers of high end gear offering warranties and a money back guarantee, but simply obligates them to file claims with shippers etc. for damaged gear, as is required by the carriers themselves in any event. The Audiogon rule focuses on items damaged in shipping for which insurance has been purchased: "Audiogon requires that Sellers are responsible for the safe transport of sold items to the Buyer. If the item is damaged or lost in transit, the Seller is expected to refund the payment to the Buyer as soon as the shipping company inspects or returns the item. The Seller will then need to recover funds from the shipping company." However, IF the item wasn't damaged in shipping, or buyer didn't want to purchase insurance, or carrier refuses to pay the insurance claim, then seller and buyer must work it out together. This site is FAR more reliable and honest in that respect than eBay and other sites. I have received damaged items from Audiogon sellers and never expected them to take the item back no questions asked, like a dealer. If you want that guarantee, buy from a dealer! Otherwise, you have to work it out together. The only time I have not been able to come to a perfectly acceptable and agreeable solution with the other party, whether I bought or sold the item, was with an eBay seller who was rude and insane. Nothing I could do about that. On Audiogon, I have never had a problem. People here, whether buying or selling, have always been reasonable and fair in my experience over several years of trading here--but I know there are those whose experience has been dramatically different. One thing I've learned is that sellers have to be persistent in following up claims with shippers because they will ALL almost ALWAYS deny an insurance claim off the bat. If you have taken digital pix of the item with its packaging and have saved receipts and invoices, though, you can ultimately prevail.
If an item has mysteriously gone bad during shipping with no visible damage to anything including the box, then buyer and seller have to agree on what to do next. There are many options. As seller, I've taken the item back and had it repaired myself, paid for the repair that the buyer arranged, given the item up to the carrier and taken insurance money to refund buyer more than he paid (since I had insured for full original price and he had only paid 50% of that original price), and various other work-outs as we have agreed. But I understood from the first few posts that some think sellers on Audiogon have dealer-like obligations to buyers and that is NOT the case here or anywhere else used items are bought and sold via internet.
The Audiogon rule quoted above and noted by Viridian does not impose such obligations.