Constant lag spikes and extreme single core CPU usage

Hi guys

I bought stardew valley on PC yesterday and have spent about 2 hours trying to get it to run right. The game completely freezes/hitches almost exactly every 3 seconds in game or even at the title screen. This started even at the beginning intro cinematic. It makes the game unplayable. I've tried reinstalling the game, reinstalled all of the visual c redistributes, reinstalled Microsoft XNA, tried all of the different resolutions and visual options, fullscreen, windowed, windowed fullscreen, etc. I've spent about an hour or more googling solutions, nothing I've come up with fixes it. Oh, also, the game uses 100% of my CPU 0 core and none others. I have a 2700X and GTX 1070 TI so it REALLY shouldn't be a problem. It's a fresh install with no mods or file tweaks. Any ideas?

I've uploaded a picture of my CPU usage after starting the game. It's at 100% regardless if I'm at the title screen or in a save.