So I had an MTX600xd that I stopped using and kept for two years. I had it tested recently, and it worked beautifully. I posted it on Craigslist, sold it, and now the purchaser is telling me that it is blown. I was wondering how can an amp be blown so fast. Should return his money? It was pushin 2 10s hard at the shop that tested it for me. He blew his diamond audio amp...IDK? he claims he went to best buy and had them test it but they say it was blown, but he has had in his possession for a month.
So he hooked it up and blew it? He needs to include more detail like what else is hooked up to his system, how the subs are wired, what gauge wire he used etc. He probably blew it himself by poor hookup, especially if it was replacing a Diamond Audio amp that had blown hooked up the same way.
It's a sketchy line. I'd be wary of refunding money when it wasn't installed by a "professional" installer (even Best Buy counts). And if you had it tested yourself before it shipped, then I wouldn't refund the money. It was working perfectly, and he had his chance to tell you if it was broken or not the day he got it.