I just had this happen today - with a new MagSafe (1) power adapter (brick) too. The brick itself doesn't get hot, nor does the MagSafe 1 plug end. Only the little adapter that has the 1->2 connection. I'm assuming it's either that the pins aren't seating right, or that there's dust or something in there that's heating up somehow. The only reason I have a MagSafe 1 brick is because I still have a MagSafe 1 MacBook, and want to have something that can charge it.
I'd really like it if Apple would just sell the cords themselves, without the brick. (like they do for the USB->Lightning/USB-C cables). Because it's ALWAYS the cord that frays/breaks, while the brick is (I presume) fine. If nothing else, this is an enormous waste of materials.. I don't know how much of the plastic/coil metal/rare-earth-metals-from-the-transistors-ICs that Apple Recycling can get out of a "returned" adapter brick. But being able to just replace the cord would be wonderful. Until Apple figures out how to make one that doesn't fray.
(Is it possible to recycle the chips themselves to extract the rare earth metals somehow? Or would it be worth it. Yes, I know (a little) about the "rare earth crisis that wasn't" in 2010 (can't find the PDF now), and I found this written in 2011:
"At the present time, there is little to no recycling of rare earth-containing products, except in Japan, but some research efforts have been started, at least in the U.S. It is likely that more research on this topic will be funded by the ROW ["non-Chinese World"] national governments. One of the major problems is that although the rare earths are essential components of electronic devices, etc., they only constitute a small fraction of weight/volume of the final product (e.g., a computer). As a result, the percentage is about the same as that of the poorer ore bodies (i.e., ~2%) which are mined today. For cell phones and portable music devices it is much worse, the rare earth magnets weigh less than 0.1% of the device."
Back to the MagSafe, wasn't the "fraying issue"/strain-relief-problems why they switched to the "L shape" plug in the first place? Why did they switch back to the T-shape?
I've though more than once about just cutting the cable in half and sticking an RCA jack in the middle, and then make a "bullet-proof-RCA-MagSafe" connector for the computer end. (Well, a 3-conductor mini-jack since it has the sense pin in there too)