I've seen the problem as well... I *think* it has always been when I was you-tubing... Very annoying because it is a complete system lock up and reboot is required.
I assumed it was (again) because I upgraded my BIOS and it was causing some issue. I had disabled IOMMU and that helped the BOOT issues, but now this occurs occasionally.
Not sure what it is, if I boot into Windows I can go on forever... never any lock ups. So it isn't hardware but has to be a driver or the kernel settings in the most recent kernels. It happens on other versions of linux (latest Fedora, Manjaro, etc.)
I have AMD 2400G, Gigabyte AB350 Gaming Wifi, NVidia 1080, 16 GB ram, tons of disk space including 2 SSDs. OS on SSD.
I've disabled the AMD APU in favor of the NVidia card.