Disclaimer: I know this may not belong in this part of the forum but I'm not sure where else to put it. Okay so here's the scoop. I recently bought a compressor on eBay. The add said that it came with a "brand new universal power supply". So when I receive the item I right away noticed the wall-wart was the wrong mA for the unit. So I ordered the right one. When I got the right supply the unit worked fine for about two to three hours... then it crapped out on me and produced a light hiss. Now what I'm doing is trying to explain to the guy I bought this from why a supply with the wrong mA is harmful to a unit. Im not extremely technical savvy so I can't explain it beyond the point of "well if you use the wrong mA it'll fry the damn thing". So I was hoping someone could give me a good answer that will help explain this to a man with a rocks for brains. By the way the supply was set to 600mA and the unit requires 1000mA. Which from what I know its worse to under power something.