I am hoping you folks can give me some opinions on what you would do in my current situation/transaction.
I listed an integrated amplifier here on Agon, a gentleman purchased it and I boxed the unit as absolutely bombproof as possible. From looking at the buyers other transactions it seems he is somewhere in South or Central America as he has a shipping agent in Miami that receives his shipments, and then sends packages on from there. It took quite a while to get to him and I received an email from him saying that the unit was not working. When I sent the unit it was in perfect working order. There is a little bit of a different turn on process with this amplifier as it has a power switch on the back that you turn on first, then you push the button on the front panel which puts the unit into standby mode. You then push that same button again to get it going into warm up mode which takes 9 seconds. I have explained this to him and the buyer says it is still not working. I then sent the instructions which I found online at the manufacturers website to make sure he understands. I don't know if there is a language barrier or not but I asked if the boxed was damaged and have not heard anything back. I would assume the buyer would have notified me if it was damaged as soon as he got the amplifier. What would you folks do in my situation? I have perfect feedback as I would never try to scam anybody and I over describe whatever I sell...I also package everything as bombproof as possible. So if the unit was working and there is no damage to the package what would you do? Refund his money and hope I get the unit back? Thanks for your insights and opinions.
Beware, this could be a scam. A friend was selling gear on Ebay and was approached for a sale like you had. Ship to a location in the USA and in turn, it would be shipped out of the country in a container, most likely. Through some detailed internet searches, he turned down the sale upon finding that the seller is still responsible for the unit even though he (or you) have no control of the piece outside the first destination in the USA. There were hundreds, if not thousands of complaints where innocent sellers were scammed out of their money.

Good luck with the resolution of this case.
I'm sorry but I wouldn't sell my items to S America or anywhere outside the US. There is too much risk involved. Let this be a lesson learned.
+1 to what joeind says. It could be a scam.

ALWAYS wait for the item to return before giving any money back to the buyer.

I have never seen any AgoN policy that would advise/require otherwise.

Receive your item first before issuing a refund... Period.
just like going to a store: first you hand over the cash then your item is handed to you, if you decide to return it then first you'll hand'em the item back they check it to make sure... Then you're handed your refund.
simple as that and no other way.

when you shipped it to him it was his or his agents responsibility to check for damages due to shipping and to inform him or you of the damages incurred so the shipping company you sent it through could inspect the item and verify if the damage happened through shipping. You are usually allowed a very short time period to inform your shipping company of this for good reason.
if there were no damages to the item due to shipping and it was just Doa, then he can send it back to you to inspect and then issue a refund. (Many companies require the same packaging as was used when shipped and not repackaging by the buyer to make sure it wasn't damaged in shipping)

remember though a transaction should always be based on good faith, meaning that if the item was really doa or whatever guarantees you provided him (if any was offered by you)  then he should be refunded his money once you get the item back in the same shape you sent it to him.
also hope both your electricities are the same, in other words he didn't connect a 120v item to 220v plug etc. ...
just my two cents
good luck.
John, This audiogon's article is good to print out on toilet paper before taking a snit.
Paypal rules are no product no money back period.