sadly the best buy thing works.
buy two from bestbuy and get the warranty.
return blown ones and get new. buy warranty on the new new ones and repeat.
after about 3-4 times we have the right to refuse to replace them, and yes we(i) do check all return speakers with a DMM and i examine the coil if possible for burns or rubbing, lol.
it does work, but be careful, i know BBY has taken a few people to court on fraud like this, and BBY has enough lawyers to cause a ton of legal fees for the scammer.
EDIT: not saying this is the case, just saying it is possible.