Last night my 18-year old came up to me pretty shaken, and with a slightly fried finger: The USB (C?) cable attached to his Hyper-X gaming headset had exploded at the connector next to his ear whilst playing!
He was charging it via PC at the time. Honestly, I thought the voltage from USB ports were so low that this would be next to impossible.
Anyway, be careful out there and disconnect all your charging devices before going to bed!