Going by the awful marking on the ICs, they are most certainly knockoffs or otherwise inferior product. And if they are not genuine, all bets are off.
Interesting that you say it died as soon as you used a 47uF capacitor. I wonder if there was some oscillation going on?
Otherwise, when you turn the voltage down to lowest, the IC is dropping the most voltage across it and will run hottest. I do notice you have no heatsink on these parts, but if it overheats it should shut off. How much current are you drawing during testing?
Since they work until you push them a bit, it's quite possible they are clones with some or all of the protection circuitry omitted, so instead of shutting down etc like a genuine one would, they just break instead.